639.15 is what percent of 660 - 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 660 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 660, so we can write it down as 100%=660.
4. We know, that x% equals 639.15 of the output value, so we can write it down as x%=639.15.
5. Now we have two simple equations:
1) 100%=660
2) x%=639.15
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%=660/639.15
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 639.15 is what percent of 660

100%/x%=660/639.15
(100/x)*x=(660/639.15)*x       - we multiply both sides of the equation by x
100=1.0326214503638*x       - we divide both sides of the equation by (1.0326214503638) to get x
100/1.0326214503638=x
96.840909090909=x
x=96.840909090909

now we have:
639.15 is 96.840909090909% of 660