21.5 is what percent of 125 - 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 125 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 125, so we can write it down as 100%=125.
4. We know, that x% equals 21.5 of the output value, so we can write it down as x%=21.5.
5. Now we have two simple equations:
1) 100%=125
2) x%=21.5
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%=125/21.5
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 21.5 is what percent of 125

100%/x%=125/21.5
(100/x)*x=(125/21.5)*x       - we multiply both sides of the equation by x
100=5.8139534883721*x       - we divide both sides of the equation by (5.8139534883721) to get x
100/5.8139534883721=x
17.2=x
x=17.2

now we have:
21.5 is 17.2% of 125