Question

Simplify the expression. 7C3 A. 5,040 B. 210 C. 1 D. 35

Answer 1

Answer:

35

Step-by-step explanation:

Simplify the expression. 7C3

the formula for nCr is $\frac{n!}{r!(n-r)!}$

n=7 and r= 3. Plug in 7 for n and 3 for r in the formula

$\frac{7!}{3!(7-3)!}$

$\frac{7*6*5*4*3*2*1}{(3*2*1)(4*3*2*1)}$

Cancel out 4*3*2*1 at the top and bottom

$\frac{7*6*5*4*3*2*1}{(3*2*1)}$

Cancel out 6 at the top and bottom

35

Answer 2

7 choose 3 is going to be 35