Express 81 as the sum of 9 odd numbers. - Vidyadip

Question

Express 81 as the sum of 9 odd numbers.

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Answer

We know that $n ^2$ is equal to the sum of first n odd numbers.

$81=9^2$

$=$ Sum of 9 odd numbers $=(1+3+5+7+9+11+13+15+17)$

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