naturral numbers

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by selango » Thu May 13, 2010 4:29 am
Answer is 1

only sum of 1 and its reciprocal forms an even number

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by sanju09 » Thu May 13, 2010 4:33 am
mitaliisrani wrote:The sum of a natural number and its reciprocal is an even number. How many such natural numbers exist ?

A) None
B) 1
C) 2
D) 99
E) None


OA [spoiler]B[spoiler][/spoiler]
GMAT uses the term "positive integers" for the "natural numbers".

There's only one positive integer, 1, whose reciprocal is also a positive integer, 1, and hence the sum of positive integer and its reciprocal is an even number, 2.

[spoiler]B

Interesting to see two choices crying "None", very unGMATish overall, really...
[/spoiler]
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