Question

Li has to read four books from a list of 10 books.
How many sets of four books can be made?
24
210
7

Answer 1

This is a combinations question where you're asked to find the value of \(10C4\) or\[\binom{10}{4} ={10! \over 4!(10-4)!}\]

Answer 2

Thanks i forgot the - part

Answer 3

That would help :P

Answer 4

umm i got 25200 i still need help

Answer 5

that is a little large :)

Answer 6

from what KG gave you

\[\binom{10}{4} ={10! \over 4!(10-4)!}=\frac{10*9*8*7}{4*3*2*1}=210\]

Answer 7

yeah when i canceled out the 4-3-2-1 on both and subtracted 10 by 4 the divided 151200 by 6 i got 25200

Answer 8

ohh opps thanks alot i own ya one