Answer:
21
Explanation:
Note that n! = n(n - 1)(n - 2) ..... × 3 × 2 × 1, thus
7! = 7 × 6 × 5 × 4 × 3 × 2 × 1
5! = 5 × 4 × 3 × 2 × 1
2! = 2 × 1
Hence
cancel 5 × 4 × 3 × 2 × 1 on numerator/ denominator, leaving
= = 21
7.6m questions
10.2m answers