20.4 is what percent of 318.9 - 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 318.9 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 318.9, so we can write it down as 100%=318.9.
4. We know, that x% equals 20.4 of the output value, so we can write it down as x%=20.4.
5. Now we have two simple equations:
1) 100%=318.9
2) x%=20.4
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%=318.9/20.4
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 20.4 is what percent of 318.9

100%/x%=318.9/20.4
(100/x)*x=(318.9/20.4)*x       - we multiply both sides of the equation by x
100=15.632352941176*x       - we divide both sides of the equation by (15.632352941176) to get x
100/15.632352941176=x
6.3969896519285=x
x=6.3969896519285

now we have:
20.4 is 6.3969896519285% of 318.9