GMAT Prep - DS Strange Assumption!

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Source: — Data Sufficiency |

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by amitansu » Thu Jul 03, 2008 3:54 am
The q here is confusing for me..However
Is ans 'C' here ?

Combining both we know that, J is divisible by 30 and K=1000

Any prime no which is greater than 1000 , must not be divisible by J since none of the multiple of 30 and 30 itself is divisible by any prime no. except 3.

Please suggest.

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by Ian Stewart » Thu Jul 03, 2008 5:26 am
You do not need to assume j < 1000 here. Using both statements, k = 1000 = 2^3 * 5^3; k has exactly two prime divisors (2 and 5). j is divisible by 30, so j = 30*x = 2*3*5*x, and j has at least three prime divisors (2, 3 and 5). No matter what j is, large or small, it has a greater number of distinct prime divisors than k has.
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by albertrahul » Sat Jul 05, 2008 6:57 am
Aha! That makes sense.
Thank You Ian.