Gmat prep1 ds2
This topic has expert replies
-
- Master | Next Rank: 500 Posts
- Posts: 166
- Joined: Sat Apr 18, 2009 10:41 pm
- Thanked: 9 times
- GMAT Score:770
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
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