The answer is 370 because you need to work it out.
Basically what I did was look at the first number, 12, and the answer to the equation and saw that 12 x 10 would be 120. And 360 + 10 would be 370.
It fits in perfectly.
12(370 - 360) = 120
370 - 360 = 10
12(10) = 120
So x = 370