A probability problem by A Former Brilliant Member
Probability
Level
2
How many ways can 5 girls and 5 boys be seated in one row if the girls are to be together?
The answer is 86400.
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Consider the girls as one group.
Then there are 6! = 720 ways to arrange the boys and the group of girls.
The group of girls can be arranged in 5! = 120 ways.
Thus the number of ways is 720 X 120 = 86400.