Express 81 as the sum of the first nine consecutive odd numbers.

Solution:

We have to express 81 as the sum of the first nine consecutive odd numbers.

We know that the sum of first n odd natural numbers is given by n².

Given, n² = 81

Taking square root,

n = 9

This implies the sum of the first nine consecutive odd numbers is 81.

The first nine consecutive odd numbers are 1, 3, 5, 7, 9, 11, 13, 15 and 17.

Therefore, the required sum is 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17

✦ Try This: Express 64 as the sum of the first nine consecutive odd numbers.

☛ Also Check: NCERT Solutions for Class 8 Maths

NCERT Exemplar Class 8 Maths Chapter 3 Problem 90

Express 81 as the sum of the first nine consecutive odd numbers

Summary:

On expressing 81 as the sum of the first nine consecutive odd numbers we get 1+ 3+ 5 + 7 + 9 + 11 + 13 + 15 + 17.

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