21.15 is what percent of 300 - 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 300 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 300, so we can write it down as 100%=300.
4. We know, that x% equals 21.15 of the output value, so we can write it down as x%=21.15.
5. Now we have two simple equations:
1) 100%=300
2) x%=21.15
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%=300/21.15
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 21.15 is what percent of 300

100%/x%=300/21.15
(100/x)*x=(300/21.15)*x       - we multiply both sides of the equation by x
100=14.184397163121*x       - we divide both sides of the equation by (14.184397163121) to get x
100/14.184397163121=x
7.05=x
x=7.05

now we have:
21.15 is 7.05% of 300