दो कथन S1 और S2 नीचे दिए गए हैं और उनके उपरांत एक प्रश्न दिया गया है :
- S1.n एक अभाज्य संख्या है।
- S2.n को 4 से विभाजित करने पर 1 शेष आता है।
- प्रश्न: यदि n, 10 और 20 के बीच एकमात्र प्राकृतिक संख्या है, तो n क्या है?
निम्नलिखित में से कौन-सा उपर्युक्त कथनों और प्रश्न के लिए सही है?
Read this question in English
Two Statements S1 and S2 are given below followed by a Question:
S1. n is a prime number.
S2. n leaves a remainder of 1 when divided by 4.
Question. If n is a unique natural number between 10 and 20, then what is n?
Which one of the following is correct in respect of the above Statements and the Question?
(a) S1 alone is sufficient to answer the Question. · (b) S2 alone is sufficient to answer the Question. · (c) S1 and S2 together are sufficient to answer the Question, but neither S1 alone nor S2 alone is sufficient to answer the Question. · (d) S1 and S2 together are not sufficient to answer the Question.
उत्तर और व्याख्या · explanation in English
Answer: (d) S1 और S2 एकसाथ प्रश्न का उत्तर देने के लिए पर्याप्त नहीं हैं।
Between 10 and 20 the primes are 11, 13, 17 and 19; of these, 13 and 17 both leave remainder 1 on division by 4. Even together the statements leave two possible values of n, so they are not sufficient.
- S1: n = 11, 13, 17 or 19.
- S2: n = 13 or 17 (the numbers between 10 and 20 that are 1 more than a multiple of 4).
- Together: 13 and 17 both satisfy S1 and S2, so n is still not fixed.
Remember · In number data sufficiency, list every value that fits; if more than one survives, the data are insufficient.
Question and answer: UPSC's official GS Paper II (2020, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·