Question

The mean length of 6 childrens' big finger is 12.6cm.

Answer 1

14.94 cm ( to 2 dec. places )

We require the sum totals of the 2 groups before calculating the mean of all 14

using mean = $\frac{sum}{count}$

Children's sum

12.6 = $\frac{sum}{6}$( cross-multiply )

sum = 6 × 12.6 = 75.6

Adult's sum

16.7 = $\frac{sum}{8}$( cross- multiply )

sum = 8 × 16.7 = 133.6

Total sum of all 14 = 75.6 + 133.6 = 209.2

mean = $\frac{209.2}{14}$ = 14.94 cm