Respuesta :

Answer:

210 ways

Step-by-step explanation:

The is a permution problem.

Formula for permutations of r things taken from n things is

[tex]P(n,r) = \frac{n!}{(n - r)!}[/tex]

[tex]\frac{7!}{(7 - 3)!} = \frac{7!}{4!} = 7*6*5 = 210[/tex] ways