2023 CSAT, all questions
UPSC Prelims 2023 · CSAT
Question 60: Data Interpretation
For five children with ages a < b < c < d < e; any two successive ages differ by 2 years. Question : What is the age of the youngest child ?
- Statement-1The age of the eldest is 3 times the youngest.
- Statement-2The average age of the children is 8 years.
Which one of the following is correct in respect of the above Question and the Statements ?
aThe Question can be answered by using one of the Statements alone, but cannot be answered using the other Statement alone.
bThe Question can be answered by using either Statement alone.
cThe Question can be answered by using both the Statements together, but cannot be answered using either Statement alone.
dThe Question cannot be answered even by using both the Statements together.
AnswerUPSC’s answer is (b).
The ages are a, a + 2, a + 4, a + 6, a + 8. Statement 1: eldest = 3 x youngest gives a + 8 = 3a, so a = 4. Statement 2: the average is the middle age, a + 4 = 8, so a = 4. Each statement alone fixes the youngest age at 4, so either one alone is enough.
Why each option is right or wrong
- (a) Wrong: both statements work alone.
- (b) Right: each alone gives a = 4.
- (c) Wrong: each alone is enough, so combining is unnecessary.
- (d) Wrong: each statement gives a = 4.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2023, General Studies Paper II (CSAT), Series A. The paper on upsc.gov.in.