what number makes this true 4 = 0.4 x

4 = 0.4 x

4/0.4 = x

10 = x

10 x 10

To determine the number that makes the equation 4 = 0.4x true, we need to isolate "x".

We start by dividing both sides of the equation by 0.4:
4/0.4 = (0.4x)/0.4

This simplifies to:
10 = x

Therefore, the number that makes the equation true is 10.