Carly has 3 movies that she can watch during the weekend: 1 Action movie, 1 Comedy, and 1 Drama. However, she needs to watch the Drama 3 times. Assuming Carly has time for 5 movies and intends to watch all of them, in how many ways can she do so?
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OA is[spoiler] B
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sumithshah
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Look upon it from the Action (A) and Comedy (C) perspective. Imagine there are 5 time slots - "A" can take any one of the 5 slots, and "C" can take any of the remaining 4 slots. D occupies the remaining 3 slots and order does not matter. Hence the answer is 5 * 4 ?
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4meonly
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she has 5 positions to put A, B and C
C must be repeated 3 times
so we have ABCCC
total combinations - 5!
C is repeted 3 times, so we should divide 5! by 3!
Because ABC1C2C3 is the same as ABC2C1C3
5!/3!= 20
B
C must be repeated 3 times
so we have ABCCC
total combinations - 5!
C is repeted 3 times, so we should divide 5! by 3!
Because ABC1C2C3 is the same as ABC2C1C3
5!/3!= 20
B
