Question

I think of a number. I multiply it by 7. I add 12. The result is 40. What is the number I am thinking of?​

Answer 1

The number that you are thinking of is 4. To get this answer I did the opposite of how you received your answer.
40 - 12 = 28
28 ÷ 4 = 7
The number that you are thinking of is 4.