Question
If the sum of the first n natural numbers is one seventh of the sum of their squares, $\mathrm{n}$ equals(a) 6(b) 7(c) 8(d) 10
Step 1
Step 1: The sum of the first n natural numbers is given by the formula $\frac{n(n+1)}{2}$ and the sum of the squares of the first n natural numbers is given by the formula $\frac{n(n+1)(2n+1)}{6}$. Show more…
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