79.9 is what percent of 99.9 - 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 99.9 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 99.9, so we can write it down as 100%=99.9.
4. We know, that x% equals 79.9 of the output value, so we can write it down as x%=79.9.
5. Now we have two simple equations:
1) 100%=99.9
2) x%=79.9
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%=99.9/79.9
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 79.9 is what percent of 99.9

100%/x%=99.9/79.9
(100/x)*x=(99.9/79.9)*x       - we multiply both sides of the equation by x
100=1.2503128911139*x       - we divide both sides of the equation by (1.2503128911139) to get x
100/1.2503128911139=x
79.97997997998=x
x=79.97997997998

now we have:
79.9 is 79.97997997998% of 99.9