0.8 is what percent of 1.09 - 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 1.09 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 1.09, so we can write it down as 100%=1.09.
4. We know, that x% equals 0.8 of the output value, so we can write it down as x%=0.8.
5. Now we have two simple equations:
1) 100%=1.09
2) x%=0.8
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%=1.09/0.8
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 0.8 is what percent of 1.09

100%/x%=1.09/0.8
(100/x)*x=(1.09/0.8)*x       - we multiply both sides of the equation by x
100=1.3625*x       - we divide both sides of the equation by (1.3625) to get x
100/1.3625=x
73.394495412844=x
x=73.394495412844

now we have:
0.8 is 73.394495412844% of 1.09