What is 28 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 28% of the output value, so we can write it down as x=28%.
5. Now we have two simple equations:
1) 12.9=100%
2) x=28%
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%/28%
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 28% of 12.9

12.9/x=100/28
(12.9/x)*x=(100/28)*x       - we multiply both sides of the equation by x
12.9=3.5714285714286*x       - we divide both sides of the equation by (3.5714285714286) to get x
12.9/3.5714285714286=x
3.612=x
x=3.612

now we have:
28% of 12.9=3.612