Question

The variance of first $30$ natural numbers, is

• A. $74.92$
• B. $37.98$
• C. $38.98$
• D. $noneofthese$

Answer 1

The correct option is A $74.92$

We know that the variance of first $n$ natural number is

$=\frac{n^2-1}{12}$

Put $n=30$

Therefore,

$\frac{900-1}{12}=\frac{899}{12}=74.916=74.92$

Hence, this is the answer.