Respuesta :

Answer:

126

Step-by-step explanation:

Use the formula...

9!(9-4)!(4)!

Answer:

126

Step-by-step explanation:

C(n,r) = n! / (r!(n−r)!)

9 C 4

= 9! / (4!(9 - 4)!)

= 9 x 8 x 7 x 6 x 5! / 4 x 3 x 2 x 1 x 5!

= 3024 / 24

= 126