Answer: 715 ( C )
Explanation:
C (13,4) = (13!)/(4!*9!)
So it can be done on the calculator by 13C4
13! = 13 x 12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1
4! = 4 x 3 x 2 x 1
9! = 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1
13 x 12 x 11 x 10 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1 / ( 4 x 3 x 2 x 1 x 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1 )
6,227,020,800 / 8,709,120
=715
So the correct answer is C, 715
Answer:
C. 17,160
Step-by-step explanation:
Given : Tim need to choose 4 graphic novels out of a collection of 13 .
To Find : No. of ways he can select the graphic novels.
Solution :
Since we are supposed to find the number of ways so we have to use combination over here
Formula :
[tex]_{n}C_{r}=\frac{n!}{(r)!*(n-r)!}[/tex]
Since n = 13 (given)
r = 4(given )
put the values in the given formula :
[tex]_{n}C_{r}=\frac{13!}{(4)!*(13-4)!}[/tex]
[tex]_{n}C_{r}=\frac{13!}{(4)!(9)!}[/tex]
[tex]_{n}C_{r}=\frac{13*12*11*10*9!}{(4)!*(9)!}[/tex]
[tex]_{n}C_{r}=\frac{13*12*11*10}{(4)!}[/tex]
[tex]_{n}C_{r}=\frac{13*12*11*10}{(4*3*2*1}[/tex]
[tex]_{n}C_{r}=715[/tex]
Thus , He can select graphic novels in 715 number of ways
Hence Option C is correct.
