2024 CSAT, all questions
UPSC Prelims 2024 · CSAT
Question 16: Basic Numeracy
What percent of water must be mixed with honey so as to gain 20% by selling the mixture at the cost price of honey?
a20%
b10%
c5%
d4%
AnswerUPSC’s answer is (a).
Take 100 units of honey costing ₹100, and add x units of water that costs nothing. The mixture of 100 + x units is sold at the honey's cost price per unit, so revenue is 100 + x. Profit = x on a cost of 100, and a 20% gain needs x = 20. So water must be 20% of the honey, i.e. 20 parts of water for every 100 parts of honey.
Why each option is right or wrong
- (a) Right. Revenue 120 on cost 100 is a 20% gain, with 20 parts of water per 100 of honey.
- (b) Wrong. 10 units of water give only a 10% gain.
- (c) Wrong. 5 units of water give only a 5% gain.
- (d) Wrong. 4 units of water give only a 4% gain.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2024, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.