18 is what percent of 20.42 - 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 20.42 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 20.42, so we can write it down as 100%=20.42.
4. We know, that x% equals 18 of the output value, so we can write it down as x%=18.
5. Now we have two simple equations:
1) 100%=20.42
2) x%=18
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%=20.42/18
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 18 is what percent of 20.42

100%/x%=20.42/18
(100/x)*x=(20.42/18)*x       - we multiply both sides of the equation by x
100=1.1344444444444*x       - we divide both sides of the equation by (1.1344444444444) to get x
100/1.1344444444444=x
88.148873653281=x
x=88.148873653281

now we have:
18 is 88.148873653281% of 20.42