80 is what percent of 99 - 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 99 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 99, so we can write it down as 100%=99.
4. We know, that x% equals 80 of the output value, so we can write it down as x%=80.
5. Now we have two simple equations:
1) 100%=99
2) x%=80
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%=99/80
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 80 is what percent of 99

100%/x%=99/80
(100/x)*x=(99/80)*x       - we multiply both sides of the equation by x
100=1.2375*x       - we divide both sides of the equation by (1.2375) to get x
100/1.2375=x
80.808080808081=x
x=80.808080808081

now we have:
80 is 80.808080808081% of 99