20 is what percent of 158.9 - 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 158.9 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 158.9, so we can write it down as 100%=158.9.
4. We know, that x% equals 20 of the output value, so we can write it down as x%=20.
5. Now we have two simple equations:
1) 100%=158.9
2) x%=20
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%=158.9/20
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 20 is what percent of 158.9

100%/x%=158.9/20
(100/x)*x=(158.9/20)*x       - we multiply both sides of the equation by x
100=7.945*x       - we divide both sides of the equation by (7.945) to get x
100/7.945=x
12.586532410321=x
x=12.586532410321

now we have:
20 is 12.586532410321% of 158.9