Question
Express $81$ as the sum of $9$ odd numbers.
✓
Answer
We know that $n^2$ is equal to the sum of first n odd numbers.
$81 = 9^2$
$=$ Sum of $9$ odd numbers $= (1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17)$
$81 = 9^2$
$=$ Sum of $9$ odd numbers $= (1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17)$
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