8.7 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 8.7 of the output value, so we can write it down as x%=8.7.
5. Now we have two simple equations:
1) 100%=31
2) x%=8.7
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%=31/8.7
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 8.7 is what percent of 31

100%/x%=31/8.7
(100/x)*x=(31/8.7)*x       - we multiply both sides of the equation by x
100=3.5632183908046*x       - we divide both sides of the equation by (3.5632183908046) to get x
100/3.5632183908046=x
28.064516129032=x
x=28.064516129032

now we have:
8.7 is 28.064516129032% of 31