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Question
In how many ways can a football team of 11 players be selected from 16 players? How many of these will
include 2 particular players?
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Solution
Number of ways in which 11 players can be selected out of 16 =\[{}^{16} C_{11} = \frac{16!}{11! 5!} = \frac{16 \times 15 \times 14 \times 13 \times 12}{5 \times 4 \times 3 \times 2 \times 1} = 4368\]
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