20.4 is what percent of 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 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 42, so we can write it down as 100%=42.
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%=42
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%=42/20.4
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 42

100%/x%=42/20.4
(100/x)*x=(42/20.4)*x       - we multiply both sides of the equation by x
100=2.0588235294118*x       - we divide both sides of the equation by (2.0588235294118) to get x
100/2.0588235294118=x
48.571428571429=x
x=48.571428571429

now we have:
20.4 is 48.571428571429% of 42