Question

FIND the number of combinations 8C2

Answer 1

Answer:

8c2 = 28

Step-by-step explanation:

You can plug this into your calculator (on a TI-84, it's MATH -> PRB -> 3) as 8 nCr 2.

Let's try to understand what the output means, though! The nCr function is based on Pascal's Triangle (see the attachment for a picture).

When we do 8 choose 2, we are basically thinking about having 8 possible values and 2 spots to fit them in, and we don't care about what order they're in. The probability of this is 8*7 / 2 = 28. Our answer makes sense!