8.5 is what percent of 39.99 - 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 39.99 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 39.99, so we can write it down as 100%=39.99.
4. We know, that x% equals 8.5 of the output value, so we can write it down as x%=8.5.
5. Now we have two simple equations:
1) 100%=39.99
2) x%=8.5
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%=39.99/8.5
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 8.5 is what percent of 39.99

100%/x%=39.99/8.5
(100/x)*x=(39.99/8.5)*x       - we multiply both sides of the equation by x
100=4.7047058823529*x       - we divide both sides of the equation by (4.7047058823529) to get x
100/4.7047058823529=x
21.255313828457=x
x=21.255313828457

now we have:
8.5 is 21.255313828457% of 39.99