21.5 is what percent of 310 - 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 310 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 310, so we can write it down as 100%=310.
4. We know, that x% equals 21.5 of the output value, so we can write it down as x%=21.5.
5. Now we have two simple equations:
1) 100%=310
2) x%=21.5
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%=310/21.5
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 21.5 is what percent of 310

100%/x%=310/21.5
(100/x)*x=(310/21.5)*x       - we multiply both sides of the equation by x
100=14.418604651163*x       - we divide both sides of the equation by (14.418604651163) to get x
100/14.418604651163=x
6.9354838709677=x
x=6.9354838709677

now we have:
21.5 is 6.9354838709677% of 310