138.42 is what percent of 680 - 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 680 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 680, so we can write it down as 100%=680.
4. We know, that x% equals 138.42 of the output value, so we can write it down as x%=138.42.
5. Now we have two simple equations:
1) 100%=680
2) x%=138.42
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%=680/138.42
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 138.42 is what percent of 680

100%/x%=680/138.42
(100/x)*x=(680/138.42)*x       - we multiply both sides of the equation by x
100=4.9125848865771*x       - we divide both sides of the equation by (4.9125848865771) to get x
100/4.9125848865771=x
20.355882352941=x
x=20.355882352941

now we have:
138.42 is 20.355882352941% of 680