What is the maximum value of m if the number

What is the maximum value of m if the number 

N = 35 × 45 × 55 × 60 × 124 × 75 

is divisible by 5m?

  1. 4
  2. 5
  3. 6
  4. 7

Answer

N = 35 × 45 × 55 × 60 × 124 × 75

= 5×7 × 5×9 × 5×11 × 5×12 ×124 × 5×5×3

= 56 × 7×9×11×12×124×3, which is divisible by 56 

So, m = 6.

The correct option is C.