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Question
Express 81 as the sum of first nine consecutive odd numbers.
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Solution
The first nine consecutive odd numbers are 1, 3, 5, 7, 9, 11, 13, 15 and 17.
We have: 81
As, 81 is a perfect square.
So, 81 = (9)2
= 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17
= Sum of first nine consecutive odd numbers.
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