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NDA 2020 Maths · Mathematics · Permutations and Combinations · medium

A team of 4 is chosen from 6 boys and 5 girls so that it has at most 2 girls.

Single correct option

A team of 4 is chosen from 6 boys and 5 girls so that it has at most 2 girls. The number of ways is
  1. A. 330
  2. B. 265
  3. C. 215
  4. D. 315
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Answer: (B) 265

Count by girls: 0 girls (64)=15\binom64=15; 1 girl 5(63)=1005\binom63=100; 2 girls (52)(62)=150\binom52\binom62=150. Total 15+100+150=26515+100+150=265. Total teams are (114)=330\binom{11}4=330, which ignores the condition.
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Original question written in the NDA 2020 Maths pattern and checked twice for the correct answer. Not an official question paper. How we write and check questions · Corrections policy · Report a mistake