Решение выражений с факториалами:

70!/68!*5!

8!+9!/7!

12!-10!/11!

(n+2) ! / (n-1) !

(n-2) ! / (n-4) !

70!/68!*5! = 68!*69*70 / 67!*5 = 69*70/120 = 69*7/12 = 483/12.

8!+9!/7! = 8*7! + 8 * 9*7! / 7! = 7! (8+72) / 7! = 81.

12!-10!/11! = 11*12*10! - 10! / 11*10! = 10! (132 - 1) / 11 * 10! = 131/11.

(n+2) ! / (n-1) ! = n * (n+1) (n+2) * (n-1) ! / (n-1) ! = n (n+1) (n+2).

(n-2) ! / (n-4) ! = (n-2) * (n-3) * (n-4) ! / (n-4) ! = (n-2) (n-3)