JEE Mains · Maths · STD 11 - 6. permutation and combination
In a group of 3 girls and 4 boys, there are two boys \(B_1\) and \(B_2\). The number of ways, in which these girls and boys can stand in a queue such that all the girls stand together, all the boys stand together, but \(B_1\) and \(B_2\) are not adjacent to each other, is :
- A 96
- B 144
- C 120
- D 72
Answer & Solution
Correct Answer
(B) 144
Step-by-step Solution
Detailed explanation
Total - when \(\mathrm{B}_1\) and \(\mathrm{B}_2\) are together \(=2!(3!4!)-2!(3!(3!2!))=144\)
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