Question 185518: can someone please help me solve this. thanks
From a group of 18 customers,5 are to be chosen to receive a special gift. Assuming that the order in which the customers are chosen is irrelevant, how many groups of 5 customers can be chosen?
Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! a From a group of 18 customers,5 are to be chosen to receive a special gift. Assuming that the order in which the customers are chosen is irrelevant, how many groups of 5 customers can be chosen?
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18C5 = 8568
Cheers,
Stan H.
Answer by Alan3354(69443)  (Show Source):
You can put this solution on YOUR website! can someone please help me solve this. thanks
From a group of 18 customers,5 are to be chosen to receive a special gift. Assuming that the order in which the customers are chosen is irrelevant, how many groups of 5 customers can be chosen?
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The 1st one chosen can be one of 18, the 2nd 1/17, 3rd 1/16, etc., so there are 18*17*16*15*14 possibilities.
But, since ABCDE is the same group as ADCEB, we have to divide by 5*4*3*2*1, since each of the had that many chances to be picked.
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So it's 18*17*16*15*14/5*4*3*2*1 = 1028190/120
= 8568 possibilities
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This is 18!/((18-5)!*5!), btw
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