Fractions

Scope of this document

The following is a background literature for teachers. It summarises the things to be known to a teacher to teach this topic more effectively. This literature is meant to be a ready reference for the teacher to develop the concepts, inculcate necessary skills, and impart knowledge in fractions from Class 6 to Class 10.

It is a well known fact that teaching and learning fractions is a complicated process in primary and middle school. Although much of fractions is covered in the middle school, if the foundation is not holistic and conceptual, then topics in high school mathematics become very tough to grasp. Hence this documents is meant to understand the research that has been done towards simplifying and conceptually understanding topics of fractions.

It is also very common for the school system to treat themes in a separate manner. Fractions are taught as stand alone chapters. In this resource book an attempt to connect it to other middle school topics such as Ratio Proportion, Percentage and high school topics such as rational, irrational numbers and inverse proportions are made. These other topics are not discussed in detail themselves, but used to show how to link these other topics with the already understood concepts of fractions.

Also commonly fractions are always approached by teaching it through one model or interpretation namely the part-whole model where the whole is divided into equal parts and the fraction represents one or more of the parts. The limitations of this method, especially in explaining mixed fractions, multiplication and division of fractions be fractions has led to educators using other interpretations such as equal share and measure. These approaches to fraction teaching are discussed.

Also a brief understanding of the common errors that children make when it comes to fractions are addressed to enable teachers to understand the child's levels of conceptual understanding to address the misconceptions.

= Syllabus =

= Concept Map =

= Theme Plan =

= Curricular Objectives = = Different Models used for Learning Fractions =
 * 1) Conceptualise and understand algorithms for basic 	operations (addition, subtraction, multiplication and division) on 	fractions.
 * 2) Apply the understanding of fractions as simple 	mathematics models.
 * 3) Understand the different mathematical terms associated 	with fractions.
 * 4) To be able to see multiple interpretations of fractions 	such as in measurement, ratio and proportion, quotient, 	representation of decimal numbers, percentages, understanding 	rational and irrational numbers.

Part-Whole
The most commonly used model is the part whole model where where the whole is divided into equal parts and the fraction represents one or more of the parts.



Half (½) : The whole is divided into '''two equal '''parts.

One part is coloured, this part represents the fraction ½.



One-Fourth (1/4) : The whole is divided into '''four equal '''parts.

One part is coloured, this part represents the fraction ¼.



One (2/2 or 1) : The whole is divided into '''two equal '''parts.

Two part are coloured, this part represents the fraction 2/2

which is equal to the whole or 1.

Two Fifth (2/5) : The whole is divided into '''five equal '''parts.

Two part are coloured, this part represents the fraction 2/5.

Three Seventh (3/7) : The whole is divided into '''seven equal '''parts.

Three part are coloured, this part represents the fraction 3/7.



Seven tenth (7/10) : The whole is divided into '''ten equal '''parts.

Seven part are coloured, this part represents the fraction 7/10.

Terms Numerator and Denominator and their meaning

Three Eight (3/8) The whole is divided into '''eight equal '''parts.

Three part are coloured, this part represents the fraction 3/8.

3/8 is also written as '''numerator/denominator. '''Here the number above the line- numerator tells us '''HOW MANY PARTS '''are involved. It 'enumerates' or counts the coloured parts.

The number BELOW the line tells – denominator tells us WHAT KIND OF PARTS the whole is divided into. It 'denominates' or names the parts.

Equal Share
In the equal share interpretation the fraction m/n denotes one share when m identical things are shared equally among n. The relationships between fractions are arrived at by logical reasoning (Streefland, 1993). For example  5/6 is the share of one child when 5 rotis (disk-shaped handmade bread) are shared equally among 6 children. The sharing itself can be done in more than one way and each of them gives us a relation between fractions. If we first distribute 3 rotis by dividing each into two equal pieces and giving each child one piece each child gets 1⁄2 roti. Then the remaining 2 rotis can be distributed by dividing each into three equal pieces giving each child a piece. This gives us the relations



The relations 3/6 = 1⁄2 and 2/6 = 1/3 also follow from the process of distribution. Another way of distributing the rotis would be to divide the first roti into 6 equal pieces give one piece each to the 6 children and continue this process with each of the remaining 4 rotis. Each child gets a share of rotis from each of the 5 rotis giving us the relation



It is important to note here that the fraction symbols on both sides of the equation have been arrived at simply by a repeated application of the share interpretation and not by appealing to prior notions one might have of these fraction symbols. In the share interpretation of fractions, unit fractions and improper fractions are not accorded a special place.

Also converting an improper fraction to a mixed fraction becomes automatic. 6/5 is the share that one child gets when 6 rotis are shared equally among 5 children and one does this by first distributing one roti to each child and then sharing the remaining 1 roti equally among 5 children giving us the relation



Share interpretation does not provide a direct method to answer the question ‘how much is the given unknown quantity’. To say that the given unknown quantity is 3⁄4 of the whole, one has figure out that four copies of the given quantity put together would make three wholes and hence is equal to one share when these three wholes are shared equally among 4. Share 'interpretation is also the quotient interpretation of fractions in the sense that 3⁄4 = 3 ÷ 4 and this is important for developing students’ ability to solve problems involving multiplicative and linear functional relations. '

'''Introducing Fractions Using Share and Measure Interpretations '''

One of the major difficulties a child faces with fractions is making sense of the symbol m/n. In order to facilitate students’ understanding of fractions, we need to use certain models. Typically we use the area model in both the measure and share interpretation and use a circle or a rectangle that can be partitioned into smaller pieces of equal size. Circular objects like roti that children eat every day have a more or less fixed size. Also since we divide the circle along the radius to make pieces, there is no scope for confusing a part with the whole. Therefore it is possible to avoid explicit mention of the whole when we use a circular model. Also, there is no need to address the issue that no matter how we divide the whole into n equal parts the parts will be equal. However, at least in the beginning we need to instruct children how to divide a circle into three or five equal parts and if we use the circular model for measure interpretation, we would need ready made teaching aids such as the circular fraction kit for repeated use.

Rectangular objects (like cake) do not come in the same size and can be divided into n equal parts in more than one way. Therefore we need to address the issues (i) that the size of the whole should be fixed (ii) that all 1⁄2’s are equal– something that children do not see readily. The advantage of rectangular objects is that we could use paper models and fold or cut them into equal parts in different ways and hence it easy to demonstrate for example that 3/5 = 6/10 using the measure interpretation.

Though we expose children to the use of both circles and rectangles, from our experience we feel circular objects are more useful when use the share interpretation as children can draw as many small circles as they need and since the emphasis not so much on the size as in the share, it does not matter if the drawings are not exact. Similarly rectangular objects would be more suited for measure interpretation for, in some sense one has in mind activities such as measuring the length or area for which a student has to make repeated use of the unit scale or its subunits.

Measure Model
Measure interpretation defines the unit fraction 1/n as the measure of one part when one whole is divided into n equal parts. The ''composite fraction m/n '' is as the measure of m such parts. Thus ''5/6  is made of 5 piece units of size 1/5 each and 6/5 is made of 6 piece units of size 1/5'' each. Since 5 piece units of size make a whole, we get the relation 6/5 = 1 + 1/5.

Significance of measure interpretation lies in the fact that it gives a direct approach to answer the ‘how much’ question and the real task therefore is to figure out the appropriate n so that finitely many pieces of size will be equal to a given quantity. In a sense then, the measure interpretation already pushes one to think in terms of infinitesimal quantities. Measure interpretation is different from the part whole interpretation in the sense that for measure interpretation we fix a certain unit of measurement which is the whole and the unit fractions are sub-units of this whole. The unit of measurement could be, in principle, external to the object being measured.

Key vocabulary:

 * 1) 1. (a) A fraction 	is a number representing a part of a whole. The whole may be a 	single object or a group of objects.   (b) When expressing a 	situation of counting parts to write a fraction, it must be ensured 	that all parts are equal.
 * 2) In 	[[Image:Fractions-Resource_Material_Subject_Teacher_Forum_September_2011_html_m2988e86b.gif]], 	5 is called the numerator and 7 is called the denominator.
 * 3) Fractions can be 	shown on a number line. Every fraction has a point associated with 	it on the number line.
 * 4) In a proper 	fraction, the numerator is less than the denominator. The 	fractions, where the numerator is greater than the denominator are 	called improper fractions.
 * 5) An improper 	fraction can be written as a combination of a whole and a 	part, and such fraction then called mixed fractions.
 * 6) Each proper or 	improper fraction has many equivalent fractions. To find an 	equivalent fraction of a given fraction, we may multiply or divide 	both the numerator and the denominator of the given fraction by the 	same number.
 * 7) A fraction is said 	to be in the simplest (or lowest) form if its numerator and the 	denominator have no common factor except 1.

Additional resources :

 * 1) [] 	 Video on teaching fractions using the equal share method made by 	Eklavya an NGO based in Madhya Pradesh, India
 * 2) [] 	Mathematics resources from Homi Baba Centre for Science Education

= Errors with fractions = When fractions are operated erroneously like natural numbers, i.e. treating the numerator and the denominators separately and not considering the relationship between the numerator and the denominator is termed as N-Distracter. For example 1/3 + ¼ are added to result in 2/7. Here 2 units of the numerator are added and 3 &amp; four units of the denominator are added. This completely ignores the relationship between the numerator and denominator of each of the fractions. Streefland (1993) noted this challenge as N-distrators and a slow-down of learning when moving from the concrete level to the abstract level.

The five levels of resistance to N-Distracters that a child develops are:


 * 1) Absence of cognitive conflict: The child is 	unable to recognize the error even when she sees the same operation 	performed resulting in a correct answer. The child thinks both the 	answers are the same in spite of different results. Eg. ½ + ½ she 	erroneously calculated as 2/4. But when the child by some other 	method, say, through manipulatives (concrete) sees ½ + ½ = 1 does 	not recognize the conflict.
 * 2) Cognitive conflict takes place: The student sees a 	conflict when she encounters the situation described in level 1 and 	rejects the ½+1/2 = 2/4 solution and recognizes it as incorrect. 	She might still not have a method to arrive at the correct solution.
 * 3) Spontaneous refutation of N-Distracter errors: The 	student may still make N-Distracter errors, but is able to detect 	the error for herself. This detection of the error may be followed 	by just rejection or explaining the rejection or even by a correct 	solution.
 * 4) Free of N-Distracter: The written work is free of 	N-Distracters. This could mean a thorough understanding of the 	methods/algorithms of manipulating fractions.
 * 5) Resistance 	to N-Distracter: The 	student is completely free (conceptually and algorithmically) of 	N-Distracter errors.

Key vocabulary:

 * 1) N-Distractor: 	 as defined above.

Additional resources:
= Operations on Fractions =
 * 1) www.merga.net.au/publications/counter.php?pub=pub_conf&id=1410 	 A PDF Research paper titled Probing Whole Number Dominance with 	Fractions.
 * 2) www.merga.net.au/documents/RP512004.pdf 	 A PDF research paper titled “Why You Have to Probe to Discover 	What Year 8 Students Really Think About Fractions ”
 * 3) []ciwrA&sig=DcM0mi7r1GJlTUbZVq9J0l53Lrc&hl=en&ei=0xJBTvLjJ8bRrQfC3JmyBw&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBUQ6AEwAA 	A google book Fractions 	in realistic mathematics education: a paradigm of developmental By 	Leen Streefland

Addition and Subtraction
Adding and subtracting like fractions is simple. It must be emphasised thought even during this process that the parts are equal in size or quantity because the denominator is the same and hence for the result we keep the common denominator and add the numerators.

Adding and subtracting unlike fractions requires the child to visually understand that the parts of each of the fractions are differing in size and therefore we need to find a way of dividing the whole into equal parts so that the parts of all of the fractions look equal. Once this concept is established, the terms LCM and the methods of determining them may be introduced.

Multiplication
Multiplying a fraction by a whole number: Here the repeated addition logic of multiplying whole numbers is still valid. 1/6 multiplied by 4 is 4 times 1/6 which is equal to 4/6.



Multiplying a fraction by a fraction: In this case the child is confused as repeated addition does not make sense. To make a child understand the of operator we can use the language and demonstrate it using the measure model and the area of a rectangle.

The area of a rectangle is found by multiplying side length by side length. For example, in the rectangle below, the sides are 3 units and 9 units, and the area is 27 square units.



We can apply that idea to fractions, too.


 * The one side of the rectangle is 1 unit (in terms of length).
 * The other side is 1 unit also.
 * The whole rectangle also is 1 square unit, in terms of area.

See figure below to see how the following multiplication can be shown.





'''Remember: '''The two fractions to multiply represent the length of the sides, and the answer fraction represents area.

Division
Dividing a fraction by a whole number can be demonstrated just like division of whole numbers. When we divide 3/4 by 2 we can visualise it as dividing 3 parts of a whole roti among 4 people.



Here 3/4 is divided between two people. One fourth piece is split into two. Each person gets 1/4 and 1/8.



OR



Another way of solving the same problem is to split each fourth piece into 2.

This means we change the 3/4 into 6/8.



When dividing a fraction by a fraction, we use the measure interpretation.



When we divide 2 by ¼ we ask how many times does ¼ fit into 2



It fits in 4 times in each roti, so totally 8 times.

We write it as

Key vocabulary:

 * 1) Least Common 	Multiple: In arithmetic and 	number theory, the least common multiple (also called the lowest 	common multiple or smallest common multiple) of two integers a 	and b, 	usually denoted by LCM(a, 	b), 	is the smallest positive integer that is a multiple of both a 	and b. 	It is familiar from grade-school arithmetic as the "lowest 	common denominator" that must be determined before two 	fractions can be added.
 * 1) Greatest Common 	Divisor: In mathematics, the 	greatest common divisor (gcd), also known as the greatest common 	factor (gcf), or highest common factor (hcf), of two or more 	non-zero integers, is the largest positive integer that divides the 	numbers without a remainder. For example, the GCD of 8 and 12 is 4.

Additional resources:
= Linking Fractions to other Topics =
 * 1) [] 	 detailed conceptual understanding of division by fractions
 * 2) [] 	understanding fractions
 * 3) [] 	 Understand how to use Geogebra a mathematical computer aided tool
 * 4) [] 	Worksheets in mathematics for teachers to use

Decimal Numbers
“Decimal” comes from the Latin root decem, which simply means ten. The number system we use is called the decimal number system, because the place value units go in tens: you have ones, tens, hundreds, thousands, and so on, each unit being 10 times the previous one.

In common language, the word “decimal number” has come to mean numbers which have digits after the decimal point, such as 5.8 or 9.302. But in reality, any number within the decimal number system could be termed a decimal number, including whole numbers such as 12 or 381.

The simplest way to link or connect fractions to the decimal number system is with the number line representation. Any scale that a child uses is also very good for this purpose, as seen in the figure below.

The number line between 0 and 1 is divided into ten parts. Each of these ten parts is 1/10, a tenth.



Under the tick marks you see decimal numbers such as 0.1, 0.2, 0.3, and so on. These are the same numbers as the fractions 1/10, 2/10, 3/10 and so on.

We can write any fraction with tenths (denominator 10) using the decimal point. Simply write after the decimal point how many tenths the number has. 0.6 means six tenths or 1/6. 1.5 means 1 whole and 5 tenths or

Note: A common error one sees is 0.7 is written as 1 /7. It is seven tenths and not one seventh. That the denominator is always 10 has to be stressed. To reinforce this one can use a simple rectangle divided into 10 parts, the same that was used to understand place value in whole numbers.

The coloured portion represents 0.6 or 6/10 and the whole block represents 1.



Percentages
Fractions and percentages are different ways of writing the same thing. When we say that a book costs Rs. 200 and the shopkeeper is giving a 10 % discount. Then we can represent the 10% as a fraction as where 10 is the numerator and the denominator is  always ''' 100'''. In this case 10 % of the cost of the book is. So you can buy the book for 200 – 20 = 180 rupees.

There are a number of common ones that are useful to learn. Here is a table showing you the ones that you should learn.

To see 40 % visually see the figure :

You can see that if the shape is divided into 5 equal parts, then 2 of those parts are shaded.

If the shape is divided into 100 equal parts, then 40 parts are shaded.

These are equivalent fractions as in both cases the same amount has been shaded.

Ratio and Proportion
It is important to understand that fractions also can be interpreted as ratio's. Stressing that a fraction can be interpreted in many ways is of vital importance. Here briefly I describe the linkages that must be established between Ratio and Proportion and the fraction representation. Connecting multiplication of fractions is key to understanding ratio and proportion.

'''What is ratio?'''

Ratio is a way of comparing amounts of something. It shows how much bigger one thing is than another. For example:

Ratio is the number of parts to a mix. The paint mix is 4 parts, with 3 parts blue and 1 part white.
 * Use 	1 measure detergent (soap) to 10 measures water
 * Use 	1 shovel (bucket) of cement to 3 shovels (buckets) of sand
 * Use 	3 parts blue paint to 1 part white

The order in which a ratio is stated is important. For example, the ratio of soap to water is 1:10. This means for every 1 measure of soap there are 10 measures of water.

Mixing paint in the ratio 3:1 (3 parts blue paint to 1 part white paint) means 3 + 1 = 4 parts in all.

3 parts blue paint to 1 part white paint = is ¾ blue paint to ¼ white paint.

Cost of a pen is Rs 10 and cost of a pencil is Rs 2. How many times the cost of a pencil is the cost of a pen? Obviously it is five times. This can be written as

The ratio of the cost of a pen to the cost of a pencil =

What is Direct Proportion ?

Two quantities are in direct proportion when they increase or decrease in the same ratio. For example you could increase something by doubling it or decrease it by halving. If we look at the example of mixing paint the ratio is 3 pots blue to 1 pot white, or 3:1.

Paint pots in a ratio of 3:1



But this amount of paint will only decorate two walls of a room. What if you wanted to decorate the whole room, four walls? You have to double the amount of paint and increase it in the same ratio.

If we double the amount of blue paint we need 6 pots.

If we double the amount of white paint we need 2 pots.

Six paint pots in a ratio of 3:1

The amount of blue and white paint we need increase in direct proportion to each other. Look at the table to see how as you use more blue paint you need more white paint:

Pots of blue paint	3	6	9	12

Pots of white paint	1	2	3	 4

Two quantities which are in direct proportion will always produce a graph where all the points can be joined to form a straight line.

'''What is Inverse Proportion ?'''

Two quantities may change in such a manner that if one quantity increases the the quantity decreases and vice-versa. For example if we are building a room, the time taken to finish decreases as the number of workers increase. Similarly when the speed increases the time to cover a distance decreases. Zaheeda can go to school in 4 different ways. She can walk, run, cycle or go by bus.

Study the table below, observe that as the speed increases time taken to cover the distance decreases

As Zaheeda doubles her speed by running, time reduces to half. As she increases her speed to three times by cycling, time decreases to one third. Similarly, as she increases her speed to 15 times, time decreases to one fifteenth. (Or, in other words the ratio by which time decreases is inverse of the ratio by which the corresponding speed increases). We can say that speed and time change inversely in proportion.

Moving from Additive Thinking to Multiplicative Thinking
Avinash thinks that if you use 5 spoons of sugar to make 6 cups of tea, then you would need 7 spoons of sugar to make 8 cups of tea just as sweet as the cups before. Avinash would be using an 'additive transformation; 'he thinks that since we added 2 more cups of tea from 6 to 8. To keep it just as sweet he would need to add to more spoons of sugar. What he does not know is that for it to taste just as sweet he would need to preserve the ratio of sugar to tea cup and use multiplicative thinking. He is unable to detect the ratio.

Proportional Reasoning
'Proportional thinking' involves the ability to understand and compare ratios, and to predict and produce equivalent ratios. It requires comparisons between quantities and also the relationships between quantities. It involves quantitative thinking as well as qualitative thinking. A feature of proportional thinking is the multiplicative relationship among the quantities and being able to recognize this relationship. The relationship may be direct (divide), i.e. when one quantity increases, the other also increases. The relationship is inverse (multiply), when an increase in one quantity implies a decrease in the other, in both cases the ratio or the rate of change remains a constant.

The process of adding involved situations such as adding, joining, subtracting, removing actions which involves the just the two quantities that are being joined, while proportional thinking is associated with shrinking, enlarging, scaling, fair sharing etc. The process involves multiplication. To be able to recognize, analyse and reason these concepts is multiplicative thinking/reasoning. Here the student must be able to understand the third quantity which is the ratio of the two quantities. The preservation of the ratio is important in the multiplicative transformation.

Rational & Irrational Numbers
After the number line was populated with natural numbers, zero and the negative integers, we discovered that it was full of gaps. We discovered that there were numbers in between the whole numbers - fractions we called them.

But, soon we discovered numbers that could not be expressed as a fraction. These numbers could not be represented as a simple fraction. These were called irrational numbers. The ones that can be represented by a simple fraction are called rational numbers. They h ad a very definite place in the number line but all that could be said was that square root of 2 is between 1.414 and 1.415. These numbers were very common. If you constructed a square, the diagonal was an irrational number. The idea of an irrational number caused a lot of agony to the Greeks. Legend has it that Pythagoras was deeply troubled by this discovery made by a fellow scholar and had him killed because this discovery went against the Greek idea that numbers were perfect.

How can we be sure that an irrational number cannot be expressed as a fraction? This can be proven algebraic manipulation. Once these "irrational numbers" came to be identified, the numbers that can be expressed of the form p/q where defined as rational numbers.

There is another subset called transcendental numbers which have now been discovered. These numbers cannot be expressed as the solution of an algebraic polynomial. "pi" and "e" are such numbers.

Vocabulary
Decimal Numbers, Percentages, Ratio, Direct Proportion, Inverse Proportion, Rational Numbers, Irrational Numbers

Additional Resources
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= Activities : =

Objective:
Introduce fractions using the part-whole method

Procedure:
Do the six different sections given in the activity sheet. For each section there is a discussion point or question for a teacher to ask children.

After the activity sheet is completed, please use the evaluation questions to see if the child has understood the concept of fractions

'''Material/Activity Sheet'''


 * 1) Write 	the Number Name and the number of the picture like the example   [[Image:Fractions-Resource_Material_Subject_Teacher_Forum_September_2011_html_m1d9c88a9.gif]]Number 	Name = One third   Number: 	 [[Image:Fractions-Resource_Material_Subject_Teacher_Forum_September_2011_html_52332ca.gif]]

Question: What is the value of the numerator and denominator in the last figure , the answer is


 * 1) Colour 	the correct amount that represents the fractions

7/10			3/8		1/5			4/7

Question: Before colouring count the number of parts in each figure. What does it represent. Answer: Denominator


 * 1) Divide 	the circle into fractions and colour the right amount to show the 	fraction

3/5	 6/7	 1/3		 5/8		 2/5


 * 1) Draw 	the Fraction and observe which is the greater fraction – observe 	that the parts are equal for each pair



1/3 2/3 4/5 2/5 3/7	 4/7


 * 1) Draw 	the Fraction and observe which is the greater fraction – Observe 	that the parts are different sizes for each pair.



1/3 1/4 1/5 1/8 1/6	 1/2


 * 1) Solve these word 	problems by drawing
 * 2) Amar divided an 		apple into 8 equal pieces. He ate 5 pieces. He put the a   other 3 in a box. 		What fraction did Amar eat?
 * 3) There are ten 		biscuits in the box. 3 are cream biscuits. 2 are salt biscuits. 4 		are chocolate biscuits. 1 is a sugar biscuit. What fraction of the 		biscuits in the box are salt biscuits.
 * 4) Radha has 6 		pencils. She gives one to Anil and he gives one to Anita. She keeps 		the   rest. What 		fraction of her pencils did she give away?

Objective:
Proper and Improper Fractions

Procedure:
Examples of Proper and improper fractions are given. The round disks in the figure represent rotis and the children figures represent children. Cut each roti and each child figure and make the children fold, tear and equally divide the roits so that each child figure gets equal share of roti.

Material/Activity Sheet


 * 1) [[Image:Fractions-Resource_Material_Subject_Teacher_Forum_September_2011_html_55f65a3d.gif]][[Image:Fractions-Resource_Material_Subject_Teacher_Forum_September_2011_html_55f65a3d.gif]][[Image:Fractions-Resource_Material_Subject_Teacher_Forum_September_2011_html_5518d221.jpg]]If 	you want to understand proper fraction, example 5/6. In the equal 	share model , 5/6 represents the share that each child gets when 5 	rotis are divided among 6 children equally.








 * 1) If you want to 	understand improper fraction, example 8/3. In the equal share 	model , 8/3 represents the share that each child gets when 8 rotis 	are divided among 3 children equally. The child in this case will 	usually distribute 2 full rotis to each child and then try to divide 	the remaining rotis. At this point you can show the mixed fraction 	representation as 2 2/3







Evaluation Question

 * 1) What 	happens when the numerator and denominator are the same, why ?
 * 2) What 	happens when the numerator is greater than the denominator why ? How 	can we represent this in two ways ?

Objective:
Comparing-Fractions

Procedure:
Print the document Comparing-Fractions.pdf  and''' Comparing-Fractions2 a'''nd work out the activity sheet

'''Material/ Activity Sheet'''

Comparing-Fractions.pdf

Comparing-Fractions2.pdf

Evaluation Question

 * 1) Does 	the child know the symbols &gt;, &lt; and =
 * 2) What happens to 	the size of the part when the denominator is different ?
 * 3) Does it decrease 	or increase when the denominator becomes larger ?
 * 4) Can we compare 	quantities when the parts are different sizes ?
 * 5) What should we do 	to make the sizes of the parts the same ?

Objective:
To understand Equivalent Fractions

Procedure:
Print 10 copies of the document from pages 2 to 5 fractions-matching-game.pdf

Cut the each fraction part

Play memory game as described in the document in groups of 4 children.

'''Activity Sheet'''

fractions-matching-game.pdf

Evaluation Question

 * 1) What is reducing a 	fraction to the simplest form ?
 * 2) What is GCF – 	Greatest Common Factor ?
 * 3) Use 	the document simplifying-fractions.pdf
 * 4) Why are fractions 	called equivalent and not equal.

Objective:
Understand Addition of Fractions

Procedure:
Open Geogebra applications

Open link []

Move the sliders Numerator1 and Denominator1 to set Fraction 1

Move the sliders Numerator2 and Denominator2 to set Fraction 2

See the last bar to see the result of adding fraction 1 and fraction 2

'''Activity Sheet'''

Please open [] in Firefox and follow the process

When you move the sliders ask children to

Observe and describe what happens when the denominator is changed.

Observe and describe what happens when denominator changes

Observe and describe the values of the numerator and denominator and relate it to the third 	result fraction. Discuss LCM and GCF

Objective:
Understand Fraction Subtraction

Procedure:
Open Geogebra applications

Open link []

Move the sliders Numerator1 and Denominator1 to set Fraction 1

Move the sliders Numerator2 and Denominator2 to set Fraction 2

See the last bar to see the result of subtracting fraction 1 and fraction 2

'''Material/Activity Sheet'''

Please open link [] in Firefox and follow the process

When you move the sliders ask children to

observe and describe what happens when the denominator is changed.

observe and describe what happens when denominator changes

observe and describe the values of the numerator and denominator and relate it to the third result fraction. Discuss LCM and GCF

Objective:
Fractions representation of decimal numbers

Procedure:
Make copies of the worksheets decimal-tenths-squares.pdf and decimal-hundreths-tenths.pdf

Activity Sheet

decimal-tenths-squares.pdf

decimal-hundreths-tenths.pdf

Evaluation Question

 * 1) Draw a number line 	and name the fraction and decimal numbers on the number line. Take a 	print of the document decimal-number-lines-1.pdf . Ask 	students to place any fraction and decimal numbers between between 	0 and 10 on the number line
 * 2) Write 0.45, 0.68, 	0.05 in fraction form and represent as a fraction 100 square.

Objective:
Linking fractional representation and Ratio and Proportion

Procedure:
Use the NCERT Class 6 mathematics textbook chapter 12 and work out Exercise 12.1

Activity Sheet

NCERT Class6 Chapter 12 RatioProportion.pdf Exercise 12.1

Evaluation Question

 * 1) Explain what the 	numerator means in the word problem
 * 2) Explain what the 	denominator means
 * 3) Finally describe 	the whole fraction in words in terms of ratio and proportion.

Objective:
Understand Multiplication of fractions

Procedure:
Open Geogebra applications

Open link []

Move the sliders Numerator1 and Denominator1 to set Fraction 1

Move the sliders Numerator2 and Denominator2 to set Fraction 2

On the right hand side see the result of multiplying fraction 1 and fraction 2

'''Material/Activity Sheet'''

Please open []raction_MultiplyArea.html in Firefox and follow the process

When you move the sliders ask children to

observe and describe what happens when the denominator is changed.

observe and describe what happens when denominator changes

One unit will be the large square border-in blue solid lines

A sub-unit is in dashed lines within one square unit.

The thick red lines represent the fraction 1 and 2 and also the side of the quadrilateral

The product represents the area of the the quadrilateral

Evaluation Question
When two fractions are multiplied is the product larger or smaller that the multiplicands – why ?

Objective:
Understand Diviion by Fractions

Procedure:
Print out the fractionsStrips.pdf

Colour each of the unit fractions in different colours. Keep the whole unit (1) white.

Cut out each unit fraction piece.

Give examples

For example if we try the first one, See how many strips will fit exactly onto whole unit strip.

'''Material /Activity Sheet'''

fractionsStrips.pdf , Crayons, Scissors, glue

Evaluation Question
When we divide by a fraction is the result larger or smaller why ?

Objective:
Understand fraction representation and percentages

Procedure:
Please print copies of the 2 activity sheets percentage-basics-1.pdf and percentage-basics-2.pdf and discuss the various percentage quantities with the various shapes.

Then print a copy each of spider-percentages.pdf and make the children do this activity

Activity Sheet

Print out spider-percentages.pdf

Evaluation Question
What value is the denominator when we represent percentage as fraction ?

What does the numerator represent ?

What does the whole fraction represent ?

What other way can we represent a fraction whoose denominator is 100.

Objective:
Understand fraction representation and Inverse Proportion.

Procedure:
Use the NCERT Class 8 mathematics textbook chapter 13 and work out Exercise 13.1

Activity Sheet

NCERT Class 8 Chapter 13 InverseProportion.pdf Exercise 13.1

Evaluation Question

1. Given a set of fractions are they directly proportional or inversely proportional ?

2. In the word problem, identify the numerator, identify the denominator and explain what the fraction means in terms of Inverse proportions

Objective:
Understand fraction representation and rational and irrational numbers

Procedure:
Construct Koch's snowflakes.

Start with a thread of a certain length (perimeter) and using the same thread construct the following shapes (see Figure).



See how the shapes can continue to emerge but cannot be identified definitely with the same perimeter (length of the thread).

Identify the various places where pi, "e" and the golden ratio occur

Material

Thread of a certain length.

Evaluation Question
How many numbers can I represent on a number line between 1 and 2.

What is the difference between a rational and irrational number, give an example ?

What is Pi ? Why is it a special number ?

= Interesting Facts = In this article we will look into the history of the fractions, and we’ll find out what the heck that line in a fraction is called anyway.

Nearly everybody uses, or has used, fractions for some reason or another. But most people have no idea of the origin, and almost none of them have any idea what that line is even called. Most know ways to express verbally that it is present (e.g. “x over y-3,” or “x divided by y-3″), but frankly, it HAS to have a name. To figure out the name, we must also investigate the history of fractions.

The concept of fractions can be traced back to the Babylonians, who used a place-value, or positional, system to indicate fractions. On an ancient Babylonian tablet, the number



, appears, which indicates the square root of two. The symbols are 1, 24, 51, and 10. Because the Babylonians used a base 60, or sexagesimal, system, this number is (1 * 60 0 ) + (24 * 60-1 ) + (51 * 60-2 ) + (10 * 60-3 ), or about 1.414222. A fairly complex figure for what is now indicated by √2.

In early Egyptian and Greek mathematics, unit fractions were generally the only ones present. This meant that the only numerator they could use was the number 1. The notation was a mark above or to the right of a number to indicate that it was the denominator of the number 1.

The Romans used a system of words indicating parts of a whole. A unit of weight in ancient Rome was the as, which was made of 12 uncias. It was from this that the Romans derived a fraction system based on the number 12. For example, 1/12 was uncia, and thus 11/12 was indicated by deunx (for de uncia) or 1/12 taken away. Other fractions were indicated as :

10/12 dextans (for de sextans),

3/12 quadrans (for quadran as)

9/12 dodrans (for de quadrans),

2/12 or 1/6 sextans (for sextan as)

8/12 bes (for bi as) also duae partes (2/3)

1/24 semuncia (for semi uncia)

7/12 septunx (for septem unciae)

1/48 sicilicus

6/12 or 1/2 semis (for semi as)

1/72 scriptulum

5/12 quincunx (for quinque unciae)

1/144 scripulum

4/12 or 1/3 triens (for trien as)

1/288 scrupulum

This system was quite cumbersome, yet effective in indicating fractions beyond mere unit fractions.

The Hindus are believed to be the first group to indicate fractions with numbers rather than words. Brahmagupta (c. 628) and Bhaskara (c. 1150) were early Hindu mathematicians who wrote fractions as we do today, but without the bar. They wrote one number above the other to indicate a fraction.

The next step in the evolution of fraction notation was the addition of the horizontal fraction bar. This is generally credited to the Arabs who used the Hindu notation, then improved on it by inserting this bar in between the numerator and denominator. It was at this point that it gained a name, vinculum. Later on, Fibonacci (c.1175-1250), the first European mathematician to use the fraction bar as it is used today, chose the Latin word virga for the bar.

The most recent addition to fraction notation, the diagonal fraction bar, was introduced in the 1700s. This was solely due to the fact that, typographically, the horizontal bar was difficult to use, being as it took three lines of text to be properly represented. This was a mess to deal with at a printing press, and so came, what was originally a short-hand, the diagonal fraction bar. The earliest known usage of a diagonal fraction bar occurs in a hand-written document. This document is Thomas Twining’s Ledger of 1718, where quantities of tea and coffee transactions are listed (e.g. 1/4 pound green tea). The earliest known printed instance of a diagonal fraction bar was in 1784, when a curved line resembling the sign of integration was used in the Gazetas de Mexico by Manuel Antonio Valdes.

When the diagonal fraction bar became popularly used, it was given two names : virgule, derived from Fibonacci’s virga; and solidus, which originated from the Roman gold coin of the same name (the ancestor of the shilling, of the French sol or sou, etc.). But these are not the only names for this diagonal fraction bar.

According to the Austin Public Library’s website, “The oblique stroke (/) is called a separatrix, slant, slash, solidus, virgule, shilling, or diagonal.” Thus, it has multiple names.

A related symbol, commonly used, but for the most part nameless to the general public, is the “division symbol,” or ÷. This symbol is called an obelus. Though this symbol is generally not used in print or writing to indicate fractions, it is familiar to most people due to the use of it on calculators to indicate division and/or fractions.

Fractions are now commonly used in recipes, carpentry, clothing manufacture, and multiple other places, including mathematics study; and the notation is simple. Most people begin learning fractions as young as 1st or 2nd grade. The grand majority of them don’t even realize that fractions could have possibly been as complicated as they used to be, and thus, don’t really appreciate them for their current simplicity.

= ANNEXURE A – List of activity sheets attached = comparing-fractions.pdf

comparing-fractions2.pdf

fractions-matching-game.pdf

fractionstrips.pdf

NCERT Class6 Chapter 12 RatioProportion.pdf

NCERT Class8 Chapter 13 DirectInverseProportion.pdf

percentage-basics-1.pdf

percentage-basics-2.pdf

simplifying-fractions.pdf

spider-percentages.pdf