permutation & combination problem?
2015-12-03 5:30 pm
2 boys and 2 girls attend a lecture. They were told to take the first 7 seats and 2 boys must sit next to each other. In how many different possible ways can they sit themselves.
回答 (1)
2015-12-03 5:53 pm
1. 2 boys select the seats = 6 (2!)
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2. 2 girls select the seats = P(5,2)
∴ 6 (2!) P(5,2) = 240 ways
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2. 2 girls select the seats = P(5,2)
∴ 6 (2!) P(5,2) = 240 ways
收錄日期: 2021-04-18 14:34:58
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