What is 21.2 percent of 81.31 - 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 81.31 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 81.31 is 100%, so we can write it down as 81.31=100%.
4. We know, that x is 21.2% of the output value, so we can write it down as x=21.2%.
5. Now we have two simple equations:
1) 81.31=100%
2) x=21.2%
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:
81.31/x=100%/21.2%
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for what is 21.2% of 81.31

81.31/x=100/21.2
(81.31/x)*x=(100/21.2)*x       - we multiply both sides of the equation by x
81.31=4.7169811320755*x       - we divide both sides of the equation by (4.7169811320755) to get x
81.31/4.7169811320755=x
17.23772=x
x=17.23772

now we have:
21.2% of 81.31=17.23772