What is 39 percent of 12.9 - 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 12.9 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 12.9 is 100%, so we can write it down as 12.9=100%.
4. We know, that x is 39% of the output value, so we can write it down as x=39%.
5. Now we have two simple equations:
1) 12.9=100%
2) x=39%
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:
12.9/x=100%/39%
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for what is 39% of 12.9

12.9/x=100/39
(12.9/x)*x=(100/39)*x       - we multiply both sides of the equation by x
12.9=2.5641025641026*x       - we divide both sides of the equation by (2.5641025641026) to get x
12.9/2.5641025641026=x
5.031=x
x=5.031

now we have:
39% of 12.9=5.031