6C4

6C4 refers to a combination where 4 items are chosen from a set of 6 items without regard to the order in which they are chosen.

The formula for combinations is calculated as:
nCr = n! / r!(n-r)!

Therefore, in this case, 6C4 can be calculated as:
6! / 4!(6-4)!
= 720 / (24 * 2)
= 720 / 48
= 15

So, 6C4 is equal to 15.