Find the average of first 15 natural numbers.
Choose the correct choice
A) 10  B) 120  C) 15  D) 8  E) 16

Rationale: explanation : sum of first n natural numbers = n ( n + 1 ) / 2 hence , sum of first 15 natural numbers = ( 15 x 16 ) / 2 = 120 therefore , required average of = 120 / 15 = 8 answer : d
Answer: D