If ... 1=5, 2=10, 3=30, then 4=?

Your answer will be 4=120 because if you see how the pattern is going you'll notice that they are multiplying the last number to the first number. For example:

1=5, 2=10, 3=30

5 10

x 2 x 3

___ ___

10 30

So that means that:

30

x 4

___

120