Prime # question -GMAT Prep

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Prime # question -GMAT Prep

by anks17 » Fri Aug 10, 2012 8:44 am
GMAT Experts,

Can you plz confirm the right way to approach the attached question.
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Prime # question -GMAT Prep
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by adthedaddy » Fri Aug 10, 2012 9:58 am
Answer to this is (E).

You may refer following link on MGMAT forum. Its explained nicely.
https://www.manhattangmat.com/forums/for ... t1152.html

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by Birottam Dutta » Fri Aug 10, 2012 10:05 am
Good question!!!

If we break down h(100), we get, h(100) = 2*4*6*......100 = 2^50 (1*2*3*4...*50)

So, h(100) contains all natural numbers upto 50.

Hence, h(100) + 1 cannot have a prime number less than 50 because it will always yield a reminder of 1.

Hence, least prime factor of h(100) + 1 will be greater than 50.

Answer is E!