What is 12.8 percent of 2.21 - 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 2.21 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 2.21 is 100%, so we can write it down as 2.21=100%.
4. We know, that x is 12.8% of the output value, so we can write it down as x=12.8%.
5. Now we have two simple equations:
1) 2.21=100%
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:
2.21/x=100%/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 what is 12.8% of 2.21

2.21/x=100/12.8
(2.21/x)*x=(100/12.8)*x       - we multiply both sides of the equation by x
2.21=7.8125*x       - we divide both sides of the equation by (7.8125) to get x
2.21/7.8125=x
0.28288=x
x=0.28288

now we have:
12.8% of 2.21=0.28288