How many combinations of 6 numbers are there in 13 numbers?

Answer 1

n = 13

r = 6

(note: "!" is used to represent "factorial")

The correct formula to use depends upon whether or not order is important.

If x,y is considered the same as y,xthen:

Number of combinations = n! / (r! (n - r)!)

= 13! / (6! (13 - 6)!)

= 13! / (6! * 7!)

= 6,227,020,800 / (720 * 5,040)

= 1,716

If x,y is considered different to y,xthen:

Number of combinations = n! / (n - r)!

= 13! / (13 - 6)!

= 13! / 7!

= 6,227,020,800 / 5,040

= 1,235,520