If we add 4 to -11, we get -7
The problem says "A number divided by 3 is four more than -11"
We have the number that is four more than -11 (which is -7). All we need to do is multiply -7 by 3 to get our answer (which is -21).
We can show this in an equation where x = number we are finding....
x/3 = (-11 + 4)
Multiply both sides by 3
x = 3(-7) = -21