Question

Mr. Gaffy asked his students to pick a number, add

3 to it, multiply by 5 and then reduce it by 12.
Jermaine calls out his answer of 15. What number
did Jermaine start with?

Answer 1

He multiplied 3 and 5 and got 15

Answer 2

2.4

Explanation:

We must do the inverse of every operation:

15 + 12 = 27

27/5 = 5.4

5.4 - 3 = 2.4