28 is what percent of 31.5 - 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 31.5 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 31.5, so we can write it down as 100%=31.5.
4. We know, that x% equals 28 of the output value, so we can write it down as x%=28.
5. Now we have two simple equations:
1) 100%=31.5
2) x%=28
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%=31.5/28
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 28 is what percent of 31.5

100%/x%=31.5/28
(100/x)*x=(31.5/28)*x       - we multiply both sides of the equation by x
100=1.125*x       - we divide both sides of the equation by (1.125) to get x
100/1.125=x
88.888888888889=x
x=88.888888888889

now we have:
28 is 88.888888888889% of 31.5