390.7 is what percent of 645 - 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 645 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 645, so we can write it down as 100%=645.
4. We know, that x% equals 390.7 of the output value, so we can write it down as x%=390.7.
5. Now we have two simple equations:
1) 100%=645
2) x%=390.7
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%=645/390.7
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 390.7 is what percent of 645

100%/x%=645/390.7
(100/x)*x=(645/390.7)*x       - we multiply both sides of the equation by x
100=1.6508830304582*x       - we divide both sides of the equation by (1.6508830304582) to get x
100/1.6508830304582=x
60.573643410853=x
x=60.573643410853

now we have:
390.7 is 60.573643410853% of 645