We assume, that the number 128 is 100% - because it's the output value of the task. 2. We assume, that x is the value we are looking for. 3. If 128 is 100%, so we can write it down as 128=100%. 4. We know, that x is 51% of the output value, so we can write it down as x=51%. 5. Now we have two simple equations: 1) 128=100% 2) x=51% where left sides of both of them have the same units, and both right sides have the same units, so we can do something like that: 128/x=100%/51% 6. Now we just have to solve the simple equation, and we will get the solution we are looking for.
7. Solution for what is 51% of 128
128/x=100/51 (128/x)x=(100/51)x - we multiply both sides of the equation by x 128=1.96078431373*x - we divide both sides of the equation by (1.96078431373) to get x 128/1.96078431373=x 65.28=x x=65.28
