Question

Simplify the expression 6C4

Answer 1

use the formula

n C r = (n!)/(r!*(n-r)!)

in this case, you're plugging in n = 6 and r = 4

Answer 2

Doing so will give you this

n C r = (n!)/(r!(n-r)!)


6 C 4 = (6!)/(4!*(6-4)!)


6 C 4 = (6!)/(4!*2!)


6 C 4 = (6*5*4!)/(4!*2!)


6 C 4 = (6*5)/(2!)


6 C 4 = (6*5)/(2*1)

I'll let you finish

Answer 3

so the answer is 15. but I dont understand the excalmation point? and where you got
6 C 4 = (6*5*4!)/(4!*2!) the 5 and four next to the 6? and then you didnt multiply 4*2? i dont understand

Answer 4

Its a combination. Hope you know that.

Answer 5

something like 6! means 6*5*4*3*2*1

Answer 6

! is a factorial symobol

Answer 7

you multiply all the positive integers less than that value til you reach 1

Answer 8

another example: 9! = 9*8*7*6*5*4*3*2*1

Answer 9

the reason why I stopped at 4! is because there's a 4! already in the denominator

so the two copies of 4! will cancel

Answer 10

and you cannot say 2*4! = 8

this is because 4! isn't just 4, it's really 4*3*2*1 = 24

Answer 11

ooooh!!!! i got it now! thank you !!

Answer 12

you're welcome