80 is what percent of 509 - 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 509 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 509, so we can write it down as 100%=509.
4. We know, that x% equals 80 of the output value, so we can write it down as x%=80.
5. Now we have two simple equations:
1) 100%=509
2) x%=80
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%=509/80
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 80 is what percent of 509

100%/x%=509/80
(100/x)*x=(509/80)*x       - we multiply both sides of the equation by x
100=6.3625*x       - we divide both sides of the equation by (6.3625) to get x
100/6.3625=x
15.717092337917=x
x=15.717092337917

now we have:
80 is 15.717092337917% of 509