Difference between revisions of "1968 AHSME Problems/Problem 26"

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== Solution ==
 
== Solution ==
<math>\fbox{E}</math>
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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 <math>\fbox{E}</math>.
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(Solution Done By FrostFox)
  
 
== See also ==
 
== See also ==

Revision as of 00:33, 18 September 2018

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 $\fbox{E}$. (Solution Done By FrostFox)

See also

1968 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 25
Followed by
Problem 27
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
All AHSME Problems and Solutions

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