What is 60 percent of 21.15 - 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 21.15 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 21.15 is 100%, so we can write it down as 21.15=100%.
4. We know, that x is 60% of the output value, so we can write it down as x=60%.
5. Now we have two simple equations:
1) 21.15=100%
2) x=60%
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:
21.15/x=100%/60%
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 60% of 21.15

21.15/x=100/60
(21.15/x)*x=(100/60)*x       - we multiply both sides of the equation by x
21.15=1.6666666666667*x       - we divide both sides of the equation by (1.6666666666667) to get x
21.15/1.6666666666667=x
12.69=x
x=12.69

now we have:
60% of 21.15=12.69