JEE Mains · Maths · STD 11 - 6. permutation and combination
There are \(5\) students in class \(10,6\) students in class \(11\) and \(8\) students in class \(12.\) If the number of ways, in which \(10\) students can be selected from them so as to include at least \(2\) students from each class and at most \(5\) students from the total \(11\) students of class \(10\) and \(11\) is \(100 \mathrm{k}\), then \(\mathrm{k}\) is equal to \(......\)
- A \(240\)
- B \(245\)
- C \(270\)
- D \(238\)
Answer & Solution
Correct Answer
(D) \(238\)
Step-by-step Solution
Detailed explanation
Class \(10^{\text {th }}\) \(11^{\text {th }}\) \(12^{\text {th }}\) Total student \(5\) \(6\) \(8\) \(2\) \(3\) \(5\) \(\Rightarrow{ }^{5} C_{2} \times{ }^{6} \mathrm{C}_{3} \times{ }^{8} \mathrm{C}_{5}\) Number of selection \(2\) \(2\) \(6\)…
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