- Express \(49\) as the sum of \(7 \) odd numbers.
- Express \(121\) as the sum of \(11\) odd numbers.
- Express \(49\) as the sum of \(7 \) odd numbers.
- Express \(121\) as the sum of \(11\) odd numbers.
Solution and Explanation
We know that the sum of first \(n\) odd natural numbers is \(n^2\).
(i) \(49 = (7)^2\)
Therefore, \(49\) is the sum of first \(7\) odd natural numbers.
\(49 = 1 + 3 + 5 + 7 + 9 + 11 + 13\)
(ii) \(121 = (11)^2\)
Therefore, \(121\) is the sum of first \(11\) odd natural numbers.
\(121 = 1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 + 19 + 21\)
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