Line 4: |
Line 4: |
| ==Previous knowledge== | | ==Previous knowledge== |
| ==Solution== | | ==Solution== |
− | <math>\frac{\sum_{}^{}x}{n}=\bar x </math> <br> | + | <math>\frac{\sum x}{n}=\bar x </math> <br> |
− | <math>\frac{\sum_{}^{}fx}{n}=\bar x </math> | + | <math>\sum {x} ={\bar x \times {n}} </math> <br> |