GMAT Experts,
Can you plz confirm the right way to approach the attached question.
Prime # question -GMAT Prep
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- adthedaddy
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Answer to this is (E).
You may refer following link on MGMAT forum. Its explained nicely.
https://www.manhattangmat.com/forums/for ... t1152.html
You may refer following link on MGMAT forum. Its explained nicely.
https://www.manhattangmat.com/forums/for ... t1152.html
- Birottam Dutta
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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!
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!
Folks please check this out
https://www.youtube.com/watch?v=H7p56NzAVKc
https://www.youtube.com/watch?v=H7p56NzAVKc