21.57 is what percent of 71.9 - 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 71.9 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 71.9, so we can write it down as 100%=71.9.
4. We know, that x% equals 21.57 of the output value, so we can write it down as x%=21.57.
5. Now we have two simple equations:
1) 100%=71.9
2) x%=21.57
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%=71.9/21.57
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 21.57 is what percent of 71.9

100%/x%=71.9/21.57
(100/x)*x=(71.9/21.57)*x       - we multiply both sides of the equation by x
100=3.3333333333333*x       - we divide both sides of the equation by (3.3333333333333) to get x
100/3.3333333333333=x
30=x
x=30

now we have:
21.57 is 30% of 71.9