. If b is the product of three consecutive positive integers

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. 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
however if it is 123=6
234=24
so how it could be inferred that it is A. It should be E
because if we think st.2
then 345=60 that is not divided by 24
but 789 is divided by 24
Am I missing something?
Source: — Data Sufficiency |

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by real2008 » Fri Jul 31, 2009 10:27 am
answer is E

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by navalpike » Fri Jul 31, 2009 10:33 am
Are you sure you typed this correctly? May be S1 says that B is a multiple of 8?

We know in any three consecutive integers, at least one of the integers will be a multiple of 3 and at least one will be a multiple of 2. (1,2,3)
(1) b is a multiple of 3
This gives us something we already knew. In fact we already know that b is a multiple of 6. Thus we know that in the product of b

B = (2)(3)k

In order for B to become a multiple of 24 (2^3 x 3), we need atleast 3 more 2’s. So if statement 1 says that b is a multiple of 8, then

B = (2)(3)k
B = (2^3)m

Then B is the multiple of the LCM of 6 and 8, which is 24.