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The mean of the squares of first ten natural numbers is:
Question

The mean of the squares of first ten natural numbers is:

A.

772\frac{77}{2}​​

B.

385

C.

231

D.

112\frac{11}{2}​​

Correct option is A

Given:

First ten natural numbers: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10

Formula Used :

Mean = (Sum of observations)  (Number of observations)\frac{\text{(Sum of observations) }}{\text{ (Number of observations)}}​​

Sum of the squares of the first n natural numbers:n(n+1)(2n+1)6 \frac{n(n + 1)(2n + 1) } 6​​

Solution:

Using the formula for the sum of the squares of the first n natural numbers, where n = 10:

Sum of squares = 10(10+1)(2×10+1)6\frac{10(10 + 1)(2 \times 10 + 1) } 6​​

Sum of squares =10(11)(21)6\frac{ 10(11)(21) } 6​​

Sum of squares = 23106\frac{2310 } 6​​

Sum of squares = 385

Mean =38510=772=\frac{ 385}{10}=\frac{77}2​​

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