Q90 of 142 Page 88

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

given: 81

As we know,


(81) = (9)2 = 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 = sum of first nine consecutive odd numbers.


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Using prime factorisation, find which of the following are perfect cubes.

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