Last Sunday a certain store sold copies of Newspaper A for $1.00 each and copies of
Newspaper B for $1.25 each, and the store sold no other newspapers that day. If r
percent of the store's revenues from newspaper sales was from Newspaper A and if p
percent of the newspapers that the store sold were copies of newspaper A, which of the
following expresses r in terms of p?
A. 100p / (125  p)
B. 150p / (250  p)
C. 300p / (375  p)
D. 400p / (500  p)
E. 500p / (625  p)
700+ problem
This topic has expert replies

 Senior  Next Rank: 100 Posts
 Posts: 30
 Joined: 06 Oct 2010
I think the answer is D.
1. We need to calculate the total revenue (R).
R= (Price of newspaper A*Number of sold of Newspaper A)+(Price of newspaper B*Number of sold of Newspaper B)
= (1*P) + (1.25* (100p)) > note: if p% of the newspapers that the store sold were copies of newspaper A, then (100p)% of the newspapers that the store sold were newspaper B.
= P + 125 + 1.25P
= 125  0.25P
R% of total revenue was from newspaper A, we can rewrite it as:
r/100 = p/(1250.25p)
r = 100p/(1250.25p)
To get the answer, we need to multiply the result by 4, we get 400p/(500p) > (D).
Hope this help.
1. We need to calculate the total revenue (R).
R= (Price of newspaper A*Number of sold of Newspaper A)+(Price of newspaper B*Number of sold of Newspaper B)
= (1*P) + (1.25* (100p)) > note: if p% of the newspapers that the store sold were copies of newspaper A, then (100p)% of the newspapers that the store sold were newspaper B.
= P + 125 + 1.25P
= 125  0.25P
R% of total revenue was from newspaper A, we can rewrite it as:
r/100 = p/(1250.25p)
r = 100p/(1250.25p)
To get the answer, we need to multiply the result by 4, we get 400p/(500p) > (D).
Hope this help.
 nileshpadwal
 Newbie  Next Rank: 10 Posts
 Posts: 6
 Joined: 24 Aug 2010
 Location: Hyderabad
Answer is D.
Plug in the numbers
Let total number of newspapers sold=100 no. of A=60 no. of B=40 so p=60
Then Revenue from each A=60*1=60$ and B=40*1.25=50
So r= (60/110)*100=600/11
now Plug in p=60
400*60/(50060)=400*60/440=(600/11)=r
hence D.
Plug in the numbers
Let total number of newspapers sold=100 no. of A=60 no. of B=40 so p=60
Then Revenue from each A=60*1=60$ and B=40*1.25=50
So r= (60/110)*100=600/11
now Plug in p=60
400*60/(50060)=400*60/440=(600/11)=r
hence D.
 GMATGuruNY
 GMAT Instructor
 Posts: 15532
 Joined: 25 May 2010
 Location: New York, NY
 Thanked: 13060 times
 Followed by:1897 members
 GMAT Score:790
I too would plug in numbers. I would use smaller numbers to make the math a bit easier.deepak123gmat wrote:Last Sunday a certain store sold copies of Newspaper A for $1.00 each and copies of
Newspaper B for $1.25 each, and the store sold no other newspapers that day. If r
percent of the store's revenues from newspaper sales was from Newspaper A and if p
percent of the newspapers that the store sold were copies of newspaper A, which of the
following expresses r in terms of p?
A. 100p / (125  p)
B. 150p / (250  p)
C. 300p / (375  p)
D. 400p / (500  p)
E. 500p / (625  p)
1 copy of A sold = $1
4 copies of B sold = 4*1.25 = $5
Total sold = 1+4 = 5.
p = 1/5*100 = 20
Total revenue = 1+5 = 6.
r = 1/6*100 = 50/3. This is our target answer.
Now we plug p=20 into all the answers to see which gives us our target of 50/3.
Only answer choice D works:
(400*20)/(50020) = 8000/480 = 50/3.
The correct answer is D.
Mitch Hunt
Private Tutor for the GMAT and GRE
[email protected]
If you find one of my posts helpful, please take a moment to click on the "UPVOTE" icon.
Available for tutoring in NYC and longdistance.
For more information, please email me at [email protected].
Student Review #1
Student Review #2
Student Review #3
Private Tutor for the GMAT and GRE
[email protected]
If you find one of my posts helpful, please take a moment to click on the "UPVOTE" icon.
Available for tutoring in NYC and longdistance.
For more information, please email me at [email protected].
Student Review #1
Student Review #2
Student Review #3

 Senior  Next Rank: 100 Posts
 Posts: 30
 Joined: 06 Oct 2010