2022 CSAT, all questions
UPSC Prelims 2022 · CSAT
Question 80: Basic Numeracy
The average weight of A, B, C is 40 kg, the average weight of B, D, E is 42 kg and the weight of F is equal to that of B. What is the average weight of A, B, C, D, E and F ?
a40·5 kg
b40·8 kg
c41 kg
dCannot be determined as data is inadequate
AnswerUPSC’s answer is (c).
The total weight of A, B and C is 3 × 40 = 120 kg. The total of B, D and E is 3 × 42 = 126 kg. F weighs the same as B. The sum of all six is (A + B + C) + (D + E) + F = 120 + (126 − B) + B = 246 kg, because B cancels. The average is 246 ÷ 6 = 41 kg.
Why each option is right or wrong
- (a) 40.5 kg does not match the total of 246 kg.
- (b) 40.8 kg does not match the total of 246 kg.
- (c) Correct: 246 ÷ 6 = 41 kg.
- (d) Wrong: the data is enough, because B cancels out.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2022, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.