12.8 is what percent of 77 - 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 77 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 77, so we can write it down as 100%=77.
4. We know, that x% equals 12.8 of the output value, so we can write it down as x%=12.8.
5. Now we have two simple equations:
1) 100%=77
2) x%=12.8
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%=77/12.8
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 12.8 is what percent of 77

100%/x%=77/12.8
(100/x)*x=(77/12.8)*x       - we multiply both sides of the equation by x
100=6.015625*x       - we divide both sides of the equation by (6.015625) to get x
100/6.015625=x
16.623376623377=x
x=16.623376623377

now we have:
12.8 is 16.623376623377% of 77