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DS problem

by gabriel » Fri Mar 16, 2007 10:38 am
Source.. dont know... found it on a old file in my computer

Q.) is a+b<c+d , the LCM of a & b is equal to the HCF (GCD ) of c & d

A.) a,b,c,d are multiples of 20
B.) a+c < b+d
Last edited by gabriel on Sat Mar 17, 2007 7:59 am, edited 2 times in total.
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Source: — Data Sufficiency |
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by amitamit2020 » Sat Mar 17, 2007 7:00 am
Do not understand the Q.

Statement (B) itself is a quaestion ..?
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Re: DS problem

by gabriel » Sat Mar 17, 2007 7:56 am
...sorry abt that amit... have edited the q ... take a look at it now..
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by real2008 » Mon Jul 27, 2009 11:20 pm
what could be the answer?
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by gmat_2010 » Fri Jul 31, 2009 3:39 am
Can B be the answer? Since we are calculating HCF and LCM I assume a, b, c, d are integers. (Can negative numbers have HCF and LCM, I don't know. Can anyone tell?)

So, LCM of a and b will be >= to (greater of a and b).
HCF of c and d will be <= to (smaller of c and d).

Since, LCM = HCF:

a + b < = 2 LCM = 2 HCF < = c + d

Hence, a + b <= c + d

Equality may hold true ONLY if a, b, c, d are all equal.
Statement B says a + c < b + d.
Hence, a, b, c, d are not equal.
Therefore, a + b < c + d.

'A' can anyway be eliminated immediately by intuition. It is a useless piece of information.

Hence, my answer is B. What's the OA?
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