21.5 is what percent of 220 - 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 220 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 220, so we can write it down as 100%=220.
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%=220
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%=220/21.5
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 220

100%/x%=220/21.5
(100/x)*x=(220/21.5)*x       - we multiply both sides of the equation by x
100=10.232558139535*x       - we divide both sides of the equation by (10.232558139535) to get x
100/10.232558139535=x
9.7727272727273=x
x=9.7727272727273

now we have:
21.5 is 9.7727272727273% of 220