What is the ratio of the average of first eight prime numbers to the average of first ten even natural numbers?

7 : 8

Sum of 1st eight prime numbers =  2 + 3 + 5 + 7 + 11 + 13 + 17 + 19 = 77

Average of prime numbers = \(\frac{77}{8}\)

Sum of 1st ten even numbers = 110

Average of even numbers = \(\frac{110}{10}\) = 11

Ratio of average of both = 7:8