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3 years ago

There are 15 members of the show choir. In how many ways can you arrange 4 members in the front row when order does not matter?

2 answers:

7 0

32760 ways. Because it is a permutation it would be 15!. Which is 15*14*13*12*11*10*9*8*7*6*5*4*3*2*1

OLEGan [10]3 years ago

3 0

We need to find the number of combinations of the 15 members taken 4 at a time:
$15C4=\frac{15!}{4!11!}=\frac{15\times14\times13\times12}{4\times3\times2\times1}=1365$

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$\huge \boxed{\mathfrak{Answer} \downarrow}$

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$\large \boxed{\bf\frac{1}{5} = 0.2} \\$

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