128.7 is what percent of 319.72 - step by step solution

To get the solution, we are looking for, we need to point out what we know.

1. We assume, that the number 319.72 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 100% equals 319.72, so we can write it down as 100%=319.72.
4. We know, that x% equals 128.7 of the output value, so we can write it down as x%=128.7.
5. Now we have two simple equations:
1) 100%=319.72
2) x%=128.7
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:
100%/x%=319.72/128.7
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 128.7 is what percent of 319.72

100%/x%=319.72/128.7
(100/x)*x=(319.72/128.7)*x       - we multiply both sides of the equation by x
100=2.4842268842269*x       - we divide both sides of the equation by (2.4842268842269) to get x
100/2.4842268842269=x
40.253972225697=x
x=40.253972225697

now we have:
128.7 is 40.253972225697% of 319.72