12.9 is what percent of 18.7 - 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 18.7 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 18.7, so we can write it down as 100%=18.7.
4. We know, that x% equals 12.9 of the output value, so we can write it down as x%=12.9.
5. Now we have two simple equations:
1) 100%=18.7
2) x%=12.9
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%=18.7/12.9
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 12.9 is what percent of 18.7

100%/x%=18.7/12.9
(100/x)*x=(18.7/12.9)*x       - we multiply both sides of the equation by x
100=1.4496124031008*x       - we divide both sides of the equation by (1.4496124031008) to get x
100/1.4496124031008=x
68.983957219251=x
x=68.983957219251

now we have:
12.9 is 68.983957219251% of 18.7