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-1: The age of the eldest is 3 times the youngest.
- Statement-2: The average age of the children is 8 years.
Which one of the following is correct in respect of the above Question and the Statements?
Answer & explanation
Answer: (b) The Question can be answered by using either Statement alone.
The ages are a, a + 2, a + 4, a + 6 and a + 8. Statement 1 gives a + 8 = 3a, so a = 4; Statement 2 gives an average (the middle age) of a + 4 = 8, so a = 4. Each Statement alone answers the Question.
- Ages: a, a + 2, a + 4, a + 6, a + 8.
- Statement 1: eldest = 3 × youngest → a + 8 = 3a → a = 4. Sufficient.
- Statement 2: the average of five equally spaced ages is the middle age: a + 4 = 8 → a = 4. Sufficient.
- So either Statement alone is enough.
Remember · For equally spaced values, the average equals the middle term — a quick route to the unknown.
Question and answer: UPSC's official GS Paper II (2023, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·