0.81 is what percent of 1.25 - 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 1.25 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 1.25, so we can write it down as 100%=1.25.
4. We know, that x% equals 0.81 of the output value, so we can write it down as x%=0.81.
5. Now we have two simple equations:
1) 100%=1.25
2) x%=0.81
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%=1.25/0.81
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 0.81 is what percent of 1.25

100%/x%=1.25/0.81
(100/x)*x=(1.25/0.81)*x       - we multiply both sides of the equation by x
100=1.5432098765432*x       - we divide both sides of the equation by (1.5432098765432) to get x
100/1.5432098765432=x
64.8=x
x=64.8

now we have:
0.81 is 64.8% of 1.25