Concept:Profit depends on the number of items sold and the difference between the actual market price and the cost price.
First, obtain the missing values
r,
w, and
z from the pie-chart conditions, then use the profit equality to find the required cost price.
Explanation:The single-digit primes are
2,3,5,7.
Since
r is a product of two distinct single-digit primes and one factor is
3, the possible values are
3×5=15 and
3×7=21.
Given
w+r=33 and
w>r.
If
r=21, then
w=12, which is not greater than
21. So this case is invalid.
If
r=15, then
w=18, and indeed
18>15. Hence
r=15 and
w=18.
Now use the pie-chart angles:
P=72∘ and
S=(180−w)∘=162∘.
The remaining angle for
Q and
R is
360∘−(72∘+162∘)=126∘.
This represents
360126​×100=35% of the total items.
Given
Q=z% and
R=(z−r)%, we get
z+(z−15)=35, so
2z=50 and
z=25.
Total items bought by all buyers
=20,000.
P gets
20%, so items with
P=4,000. For
P,
A:B=3:2, hence
A=2,400 and
B=1,600.
Q gets
25%, so items with
Q=5,000.
For
Q, the percentage of item
A=(2r+z)%=(30+25)%=55%.
Thus item
A for
Q=55% of
5,000=2,750, and item
B for
Q=2,250.
From the given line graph, the actual market price of item
A for
P in 2013 is
Rs. 280.
Given the cost price of item
A for
P in 2013 is
Rs. 250.
Profit per item
=280−250=Rs. 30.
Total profit of
P on item
A in 2013
=2,400×30=Rs. 72,000.
This profit is equal to the total profit of
Q on item
B in 2015.
From the line graph, the actual market price of item
B for
Q in 2015 is
Rs. 320.
Let the required cost price be
x.
2,250×(320−x)=72,000.
So
320−x=2,25072,000​=32.
Hence
x=320−32=288.
Answer:The cost price of item
B for
Q in 2015 was
Rs. 288.
Correct option: C.