7.78 is what percent of 138 - 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 138 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 138, so we can write it down as 100%=138.
4. We know, that x% equals 7.78 of the output value, so we can write it down as x%=7.78.
5. Now we have two simple equations:
1) 100%=138
2) x%=7.78
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%=138/7.78
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 7.78 is what percent of 138

100%/x%=138/7.78
(100/x)*x=(138/7.78)*x       - we multiply both sides of the equation by x
100=17.737789203085*x       - we divide both sides of the equation by (17.737789203085) to get x
100/17.737789203085=x
5.6376811594203=x
x=5.6376811594203

now we have:
7.78 is 5.6376811594203% of 138