7! divided by (7-4) !

It would be 7*6*5*4*3*2*1 divided by 3*2*1. So just put that in your calculator/work it out and you'll have your answer.

First, let's write out (7-4) ! Simplifying, we get (3) ! = 3! = 3*2*1 = 6.

Actually, we can stop work here when we reach 3!

Then the problem consists of 7! / 3!.

7! = 7*6*5*4*3!

Dividing 7! by 3! results in 7*6*5*4 = 42*20 = 840 (answer)