Prime factors

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Prime factors

by sivaelectric » Mon May 30, 2011 5:24 am
Does the integer k have at least four different prime factors?
  • 1. k/14 is an integer
    2. k/30 is an integer
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Chitra Sivasankar Arunagiri
Source: — Data Sufficiency |

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by cans » Mon May 30, 2011 5:48 am
IMO C

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by Frankenstein » Mon May 30, 2011 5:51 am
Hi,
From(1) : k/14 is integer.
if k=14=2.7, it has 2 prime factors
if k=210=2.3.5.7, it has 4 prime factors
Insufficient

From(2) : k/30 is integer.
if k=30=2.3.5, it has 3 prime factors
if k=210=2.3.5.7, it has 4 prime factors
Insufficient

From(1)&(2)
k is a multiple of LCM(14,30). So k is a multiple of 210 = 2.3.5.7.
So, k has at least 4 prime factors
Sufficient

Hence, answer C

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by sivaelectric » Mon May 30, 2011 5:53 am
Yes OA C and thanks for the explanation Frankenstein.
If I am wrong correct me :), If my post helped let me know by clicking the Thanks button ;).

Chitra Sivasankar Arunagiri