JEE PYQ: Permutation And Combination Question 2
Question 2 - 2021 (17 Mar Shift 1)
Team ‘A’ consists of 7 boys and $n$ girls and Team ‘B’ has 4 boys and 6 girls. If a total of 52 single matches can be arranged between these two teams when a boy plays against a boy and a girl plays against a girl, then $n$ is equal to:
(1) 5
(2) 2
(3) 4
(4) 6
Show Answer
Answer: (3)
Solution
Total matches between boys $= {}^7C_1 \times {}^4C_1 = 28$. Total matches between girls $= {}^nC_1 \times {}^6C_1 = 6n$. $28 + 6n = 52 \Rightarrow n = 4$.
BETA
