Gmat prep1 ds2

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Gmat prep1 ds2

by Naruto » Wed Jul 22, 2009 3:53 am
OA later. Would appreciate detailed discussion
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by raghavsarathy » Thu Jul 23, 2009 5:55 pm
IMO - E

S.I = PTR/100

Let amounts invested in A and B be a and b

Rate of interest for A = x and for B = 3x/2


From 1

50 = ax/100 -------------- 1

150 = 3bx/200---------------2

Since we have 3 unknowns and 2 eqns we cannot solve for x

A is insufficient

From 2

we have b=2a , but no other relation b/n the two. Hence insufficent


Combining

Substitue b= 2a in eqn 2 and you end up with 3ax= 150 *100.. Which is nothing but eqn 1 * 3

We cannot solve further for a and x..

Hence E