Question

the sum of 15 observations is 42 find the mean​

Answer 1

$sum \: of \:15 \: obs. = 42$

$mean = \frac{sum \: of \: observations}{no. \: of \: observations}$

$mean = \frac{42}{15} \\ mean = 2.8$

Answer 2

Mean = No. of observations divided by

Sum of all observations

Mean = 15 divided by 420

=28