Discussion of Question with ID = 084 under Permutations-and-Combinations

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Question

Out of given 8 consonants and 4 vowels, how many words can be formed that contain 3 consonants and 2 vowels or 3 vowels and 2 consonants?

A

53760.

B

53770.

C

53750.

D

53780.

Soln.
Ans: a

We can make the selection in 4C3 × 8C2 + 4C2 × 8C3 ways. But the five members can themselves be arranged in 5! ways. So the number of words is 120 × (4C3 × 8C2 + 4C2 × 8C3) = 53760.

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