A store sells newspaper A at price of $1 and B at price of $1.25. In a certain day, if r percent of the total income is from A, and p percent of the total copies sold are A, in terms of r, p=?

A store sells newspaper A at price of $1 and B at price of $1.25. In a certain day, if r percent of the total income is from A, and p percent of the total copies sold are A, in terms of r, p=?

My answer is:
r = 100p/(p +123.75)
My method was:
i) Let x be the total copies
ii) copies of A = px/100
iii) copies of B would be: (100-p)x/100
iv) Total income from A = px/100 $
v) Total income from B = (125x-1.25px)/100
vi) Adding iv) and v) gives total income, which is: (125x+(p-1.25)x)/100
Therefore, r = 100*px/(125x+px-1.25x)…….. since r is % of total income from A.
r = px/(123.75x+px)
= p/(p+123.75)
Hi,
I think best way wud be using the figures.
Say there are 60 copies of each paper.
By selling paper A, income received = 60$
By selling paper B, income received = 75$
Total income = 135$
Now r% = 60/135 and p% = 75/135 = 5/4*r%..which is the ans reqd..
You can verify the same with any number of papers.
Suppose total 100 Copies.
A – > P Copies
B -> 100 – p Copies
Total Income = P + (100 – P)1.25
A’s Income i.e r % = (P+(100-P)1.25 )r / 100
say r= 50% then p = r * 1.25/(1+1.25)
thus p = 5/9 % (cross checked)
sorry
1.25r / (0.25r + 100)
say 50% revenues from A then p % = 1.25(50) / (.25*50 + 100) = 62.5/112.5 = 5/9
Answer should be:
p = 1.25r / (0.0025r + 1)
I got the ans: 500r / (400+r)
My answer:
Considering the ratio of incomes for B and A
(100-p) * 1.25 / p = (100-r)/r
=> p = 500 r/(r+400)
is anybody able to see the options??
GMAT TEAM plz give true answer
Total Income of A = r * x (where x=Total Income)
Total Income of B = (100 – r) * x
Total Copies of A = p * y (where y = Total Copies)
Total Copies of B = (100 – p) * y
Now ,
Total Income Of A = Total Copies of A * Amount of each copy (viz is 1)
So , r*x = p * y * 1
Hence , x/y = p/r —–(i)
Similarly , Total Income of B = Total Copies of B * Amount of each Copy (viz 1.25)
So , (100 – r) * x = (100 – p) * y
Solve n u will get , x/y = (100 – p)(1.25) / (100 – r) —–(ii)
Equate i n ii and solve u will get the answer as,
p= (125 * r) / (100 – 0.25r)
is it rt ?
Let “X” be the no. of A newspaper copies sold.
Let “Y” be the no. of B newspaper copies sold.
From the given statements:
Eq.1:
r(X+1.25Y)/100 = X
Eq. 2
p(X+Y)/100 = X
SIMPLIFICATION GIVES p = 1.125 r
p = 1.25r / (1 + 0.25r) if p and r are expressed as decimals from 0 to 1
p = 125r / (100 + 0.25r) if p and r are expressed as percentages from 0 to 100
whats the true answer????????????????
p=500r/(400+r)
lets understand the solution:
Assume,total no of copies sold=C
copies sold for A=C*p
copies sold for B=C*(100-p)
Now,
r = [(C*p*1$)/{C*p*1$+C*(100-p)*1.25$}]*100
r= 500r/(400+r)