72 is what percent of 309 - 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 309 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 309, so we can write it down as 100%=309.
4. We know, that x% equals 72 of the output value, so we can write it down as x%=72.
5. Now we have two simple equations:
1) 100%=309
2) x%=72
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%=309/72
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 72 is what percent of 309

100%/x%=309/72
(100/x)*x=(309/72)*x       - we multiply both sides of the equation by x
100=4.2916666666667*x       - we divide both sides of the equation by (4.2916666666667) to get x
100/4.2916666666667=x
23.300970873786=x
x=23.300970873786

now we have:
72 is 23.300970873786% of 309