GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
An avid reader divides his books into two overlapping collections, A
[#permalink]
14 Sep 2021, 02:50
14 Sep 2021, 02:50
1
Expert Reply
00:00
Question Stats:
100% (02:56) correct
0% (00:00) wrong based on 1 sessions
Hide Show timer Statistics
An avid reader divides his books into two overlapping collections, \(A\) and \(B\). The number of books in \(A\) is \(120\%\) percent greater than that in \(B\). The number of books common in both collections is \(20\). If collection \(B\) contains '\(n\)' books which are not in \(A\), what is the least number of books in \(A\) and \(B\) combined for the least value of \(n\)?
(A) 50
(B) 60
(C) 70
(D) 80
(E) 90
(A) 50
(B) 60
(C) 70
(D) 80
(E) 90
Re: An avid reader divides his books into two overlapping collections, A
[#permalink]
14 Sep 2021, 12:07
14 Sep 2021, 12:07
1
Let books unique to A be m, unique to B be n and common be C.
So the equation is (m + c) = 2.2(n+c). and c = 20.
which will lead to m = 2.2n + 24. The least value to give an integer is when n = 5.
So m = 35 , n = 5 and c = 20
so total books are m +n +c = 60.
Answer is B) 60.
Note: multiplication 2.2 is due to 120% increase. If 100% increase, then it's doubled, so multiply by 2....
So the equation is (m + c) = 2.2(n+c). and c = 20.
which will lead to m = 2.2n + 24. The least value to give an integer is when n = 5.
So m = 35 , n = 5 and c = 20
so total books are m +n +c = 60.
Answer is B) 60.
Note: multiplication 2.2 is due to 120% increase. If 100% increase, then it's doubled, so multiply by 2....
gmatclubot
Re: An avid reader divides his books into two overlapping collections, A [#permalink]
14 Sep 2021, 12:07
Moderators:
