UPSC Prelims 2008 · General Studies
Question 5: Basic Numeracy
A person purchases 100 pens at a discount of 10%. The net amount of money spent by the person to purchase the pens is Rs 600. The selling expenses incurred by the person are 15% on the net cost price. What should be the selling price for 100 pens in order to earn a profit of 25%?
AnswerThe answer is (c).
The Rs 600 is already the net price after the 10% discount, so it is the cost price. Selling expenses are 15% of 600 = Rs 90, making the total cost Rs 690. A 25% profit on this cost is 0.25 x 690 = Rs 172.50, so the selling price is 690 + 172.50 = Rs 862.50. Do not add the profit to Rs 600 alone.
Why each option is right or wrong
- (a) Rs 802.50 corresponds to a cost of Rs 642, not Rs 600 plus Rs 90.
- (b) Rs 811.25 corresponds to a cost of Rs 649, not Rs 690.
- (c) Cost Rs 690 plus a 25% profit gives Rs 862.50.
- (d) Rs 875 is a 25% profit on Rs 700, not on the actual cost of Rs 690.
Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2008, General Studies. UPSC's own paper isn't online; the words are from a published compilation. The paper on upsc.gov.in.