Divisible and Factors

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Source: — Data Sufficiency |

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by cramya » Mon Feb 23, 2009 2:03 pm
Stmt I

Every third number is divisible by 3. There will be atleast 1 number in the product of 4 consecutive positive integers that will be divisible by 3 so r is divisible by 3

SUFF

Stmt II

r<25

r=1 no
r= 3 yes

INSUFF

Choose A

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by relaxin99 » Mon Feb 23, 2009 3:06 pm
Great explanation thank you :o

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by x2suresh » Mon Feb 23, 2009 8:00 pm
agree with Ramya

A.

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by Ian Stewart » Fri Feb 27, 2009 1:20 pm
For related questions, you might find it helpful to know the following:

The product of n consecutive integers is always divisible by n!

So, the product of any 4 consecutive integers is always divisible by 4! = 24, so is definitely divisible by 3, by 8, by 12, or by any other factor of 24.
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