Problem:174 GMAT REVIEW QUANT

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Problem:174 GMAT REVIEW QUANT

by sameke » Sun Jan 04, 2009 10:34 pm
Hi Everybody!
I was wondering if you could help me to understand this problem, there is something fishy about it.
AB
x
BA
ACA

Question: The product of the two-digit number above is the three-digit number ACA, where A,B and C are three different nonzero digits. if AXB <10
, what is the two-digit number AB?

a)11
b)12
c)13
d)21
e)31


And now my question, why is it 21 not 12. 11, 13,31 my excluded immediately.

Thanks,
Source: — Problem Solving |

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by vivek.kapoor83 » Sun Jan 04, 2009 10:51 pm
from the stem u can figure out A*B =A that means B =1, coz anything *1 = anything,
Now look at ans choices. with value of B =1

as cal is v easy u can cal.
11*11 =121 doesnt satisfy ( As A,B are diff-given)
21*1 2 =252..>Perfect
31*13 = 403...doesnt satisfy

Hence D

Newbie | Next Rank: 10 Posts
Posts: 7
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Thanks

by sameke » Mon Jan 05, 2009 12:54 pm
To vivek.kapoor83,

Thanks,

Yeah, I just realized that it was so easy.