SOLUTION: 10C7 ———— 5P3

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Question 1140100: 10C7
————
5P3
Found 2 solutions by rothauserc, MathLover1:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
10C7 = 10! / (7! * (10-7)!) = 120
:
5P3 = 5 * 4 * 3 = 60
:
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10C7 / 5P3 = 120 / 60 = 2
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:

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
10C7+%2F5P3+
first find 10C7

10C7=n%21%2F%28%28n-r%29%21r%21%29
10C7=10%21%2F%28%2810-7%29%217%21%29
10C7=10%21%2F%283%217%21%29

10C7=10%2A3%2A4
10C7=120
then
5P3=n%21%2F%28n-r%29%21
5P3=5%21%2F%285-3%29%21
5P3=5%21%2F2%21
5P3=%285%2A4%2A3%2Across%282%2A1%29%29%2F%28cross%282%29%2A1%29
5P3=5%2A4%2A3
5P3=60


=> 10C7+%2F5P3+=120%2F60=2