JEE Mains · Maths · STD 11 - 6. permutation and combination
A class contains \(b\) boys and \(g\) girls. If the number of ways of selecting \(3\) boys and \(2\) girls from the class is \(168\), then \(b +3\,g\) is equal to.
- A \(17\)
- B \(16\)
- C \(15\)
- D \(14\)
Answer & Solution
Correct Answer
(A) \(17\)
Step-by-step Solution
Detailed explanation
\({ }^{b} C_{3} \times{ }^{g} C_{2}=168\) \(b(b-1)(b-2)(g)(g-1)=8 \times 7 \times 6 \times 3 \times 2\) \(b+3 g=17\)
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