What is 90.4 percent of 20 - 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 20 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 20 is 100%, so we can write it down as 20=100%.
4. We know, that x is 90.4% of the output value, so we can write it down as x=90.4%.
5. Now we have two simple equations:
1) 20=100%
2) x=90.4%
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:
20/x=100%/90.4%
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 90.4% of 20

20/x=100/90.4
(20/x)*x=(100/90.4)*x       - we multiply both sides of the equation by x
20=1.1061946902655*x       - we divide both sides of the equation by (1.1061946902655) to get x
20/1.1061946902655=x
18.08=x
x=18.08

now we have:
90.4% of 20=18.08