Subject
Quantitative Aptitude
Topic
Permutation & Combination
In how many ways can 5 boys and 7 girls be arranged in a row so that no two boys are together?
In how many ways can 5 boys and 7 girls be arranged in a row so that no two boys are together?
ক)
5! × 7!খ)
7p2× 5!গ)
7! × 8p5ঘ)
7p5× 7!ঙ)
None of theseExplanation
As no two boys are to be together, we need the presence of a girl between every two boys. The seven girls can be arranged in 7! Ways. _G_G_G_G_G_G_G_ The five boys can be arranged in 8 available gaps in 8 P 5 ways. ∴ the total number of arrangements = 7! × 8 p 5Related questions
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