639.7 is what percent of 31 - 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 31 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 31, so we can write it down as 100%=31.
4. We know, that x% equals 639.7 of the output value, so we can write it down as x%=639.7.
5. Now we have two simple equations:
1) 100%=31
2) x%=639.7
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%=31/639.7
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 639.7 is what percent of 31

100%/x%=31/639.7
(100/x)*x=(31/639.7)*x       - we multiply both sides of the equation by x
100=0.048460215726122*x       - we divide both sides of the equation by (0.048460215726122) to get x
100/0.048460215726122=x
2063.5483870968=x
x=2063.5483870968

now we have:
639.7 is 2063.5483870968% of 31