Question

What is the value of n(C)r when n=8 and r=7?

Answer 1

I believe it would be 8.
8(C)7 = (8!)/(7! x 1!) = 8

Answer 2

When you get to the (7! x1!) you just factor out the 7 correct?

Answer 3

I would simplify the denominator to 7! as 1! is just 1.
8! = 8 x 7 x 6 ...1
7! = 7 x 6 x 5 ... 1
Therefore everything would cancel except for the eight in the numerator.

Answer 4

Alright, that's what I had just wasn't sure. Thank you!

Answer 5

\[nCr=\frac{nPr}{r!}\]

Answer 6

i remember that easier than the other method; 8P7 is just start at 8 and pick 7

8.7.6.5.4.3.2

diivide by 7!

8.7.6.5.4.3.2
----------- = 8
7.6.5.4.3.2