पाँच बच्चों के लिए, जिनकी आयु a < b < c < d < e क्रम में है; किसी भी दो उत्तरोत्तर आयु के बीच 2 वर्षों का अंतर है ।
प्रश्न : सबसे छोटे बच्चे की आयु क्या है ?
- कथन-1: सबसे बड़े बच्चे की आयु सबसे छोटे बच्चे की आयु की तीन गुनी है ।
- कथन-2: बच्चों की औसत आयु 8 वर्ष है ।
उपर्युक्त प्रश्न और कथनों के बारे में निम्नलिखित में से कौन-सा एक सही है ?
Read this question in English
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?
(a) The Question can be answered by using one of the Statements alone, but cannot be answered using the other Statement alone. · (b) The Question can be answered by using either Statement alone. · (c) The Question can be answered by using both the Statements together, but cannot be answered using either Statement alone. · (d) The Question cannot be answered even by using both the Statements together.
उत्तर और व्याख्या · explanation in English
Answer: (b) इस प्रश्न का उत्तर, दोनों में से किसी भी एक कथन का अकेले उपयोग कर दिया जा सकता है ।
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). ·