You can put this solution on YOUR website! I'm going to assume your question was "How many committees of four students
can be formed from a class of fifteen students?".
Since the committee is a group of people you want to count the "number of combinations of size four in a group of size fifteen".
The combination answer if 15C4 which is 15!/[(15-4)! (4)!]
This is the same as [15*14*13*12]/[1*2*3*4] which the same
as 1365.
Good luck.
Cheers,
Stan H.
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