Multiple of?

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Multiple of?

by grandh01 » Tue Aug 28, 2012 10:48 pm
If b is the product of three
consecutive positive integers c, c + 1,
and c + 2, is b a multiple of 24 ?
(1) b is a multiple of 3,
(2) c is odd.

OA is A
Source: — Data Sufficiency |

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by Anurag@Gurome » Tue Aug 28, 2012 11:17 pm
grandh01 wrote:If b is the product of three
consecutive positive integers c, c + 1,
and c + 2, is b a multiple of 24 ?
(1) b is a multiple of 3,
(2) c is odd.

OA is A
We can do this by Picking numbers approach.

(1) b is a multiple of 3.
If c = 1, b = 6, here b is not a multiple of 24.
If c = 2, b = 24, here b is a multiple of 24.
No definite answer; NOT sufficient.

(2) c is odd.
If c = 1, b = 6, here b is not a multiple of 24.
If c = 7, b = 504, here b is a multiple of 24.
No definite answer; NOT sufficient.

Combining (1) and (2), c is odd and b is a multiple of 3. Here we can take the same examples as in statement 2.
If c = 1, b = 6, here b is not a multiple of 24.
If c = 7, b = 504, here b is a multiple of 24.
No definite answer; NOT sufficient.

The correct answer is E.
Anurag Mairal, Ph.D., MBA
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