Question

Find the average of the cubes of first 7 prime numbers

Answer 1

First four odd numbers are 1 , 3 , 5 , 7

Therefore their cubes = 1 ^ 3 = 1 , 3 ^ 3 = 27 , 5 ^ 3 = 125 , 7 ^ 3 = 343

First four prime numbers are 2 , 3 , 5 , 7

Therefore their cubes = 2 ^ 3 = 8 , 3 ^ 3 = 27 , 5 ^ 3 = 125 , 7 ^ 3 = 343

Since Mean = Sum / Observation

Therefore Mean = Sum of all the cubes of odd and prime numbers / The total number of observations.

i.e. 1 + 27 + 125 + 343 + 8 + 27 + 125 + 343 / 8

= 999 / 8 = 124.875