129.6 is what percent of 864 - 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 864 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 864, so we can write it down as 100%=864.
4. We know, that x% equals 129.6 of the output value, so we can write it down as x%=129.6.
5. Now we have two simple equations:
1) 100%=864
2) x%=129.6
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%=864/129.6
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 129.6 is what percent of 864

100%/x%=864/129.6
(100/x)*x=(864/129.6)*x       - we multiply both sides of the equation by x
100=6.6666666666667*x       - we divide both sides of the equation by (6.6666666666667) to get x
100/6.6666666666667=x
15=x
x=15

now we have:
129.6 is 15% of 864