GMAT Problem Solving (PS) | The number of baseball cards that John and Bill had was in the ratio o

Algebra was simple but some how i got stuck and then tried this approach and it seems to have worked.

I plugged in a value from answer choice and arrived at the correct answer through elimination. The calculations are simple so it did not take much time.

Let us pick the middle from the given answer choices=45

Therefore John has 45 more caps than bill.

Let bill have X caps than john will have X+45 caps. Set up the equation-Take 2nd ratio.
J/B=X+45/X=3/2
X(Bill)=90.
No of caps John has is 90+45=135
The
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