Question

What will come in place of question mark?

15 × 6 = ? × 6 + 5 × 6

Answer 1

15 can be written as
15 = 1+14
15= 2+13
15 = 3+12
15= 4 + 11
15= 5 + 10 and so on

Here we already have 5 , hence to get 15 we must have 10
15 × 6 = (10 + 5) × 6
= 10× 6 + 5 × 6

Thus, 10 will come in place of question mark.