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Is 1 Prime Number??

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by rahul26 » Mon May 04, 2009 11:25 am
Hi,
Till date I was under the impression that 1 is neither prime nor composite.
But the explanations given by OG11 for question 118 is considering 1 as prime. Please let me know whether to consider 1 as prime or not while solving DS.
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Re: Is 1 Prime Number??

by dumb.doofus » Mon May 04, 2009 12:04 pm
rahul26 wrote:Hi,
Till date I was under the impression that 1 is neither prime nor composite.
But the explanations given by OG11 for question 118 is considering 1 as prime. Please let me know whether to consider 1 as prime or not while solving DS.
You got eyes of a hawk man!! :-) Very well observed.. I agree with you.. that's a mistake in OG.

1 is not a prime number.
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by Ian Stewart » Mon May 04, 2009 12:08 pm
That's Q118 in the DS section of OG11, and yes, it's a mistake. 1 is definitely not a prime number. I pointed out that error and two others in OG11 here:

https://gmatix.com/blogging/index.php?x=30
For online GMAT math tutoring, or to buy my higher-level Quant books and problem sets, contact me at ianstewartgmat at gmail.com

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