1968 AHSME Problems/Problem 26

Problem

Let $S=2+4+6+\cdots +2N$, where $N$ is the smallest positive integer such that $S>1,000,000$. Then the sum of the digits of $N$ is:

$\text{(A) } 27\quad \text{(B) } 12\quad \text{(C) } 6\quad \text{(D) } 2\quad \text{(E) } 1$

Solution

Note that $S = 2(1+2+3+...+N) = N(N +1)$. It follows that $N = 1000$, so the sum of the digits of $N$ is $\fbox{E}$.


FrostFox

See also

1968 AHSC (ProblemsAnswer KeyResources)
Preceded by
Problem 25
Followed by
Problem 27
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