81 is what percent of 102 - 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 102 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 102, so we can write it down as 100%=102.
4. We know, that x% equals 81 of the output value, so we can write it down as x%=81.
5. Now we have two simple equations:
1) 100%=102
2) x%=81
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%=102/81
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 81 is what percent of 102

100%/x%=102/81
(100/x)*x=(102/81)*x       - we multiply both sides of the equation by x
100=1.25925925926*x       - we divide both sides of the equation by (1.25925925926) to get x
100/1.25925925926=x
79.4117647059=x
x=79.4117647059

now we have:
81 is 79.4117647059% of 102