78.21 is what percent of 1580 - 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 1580 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 1580, so we can write it down as 100%=1580.
4. We know, that x% equals 78.21 of the output value, so we can write it down as x%=78.21.
5. Now we have two simple equations:
1) 100%=1580
2) x%=78.21
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%=1580/78.21
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 78.21 is what percent of 1580

100%/x%=1580/78.21
(100/x)*x=(1580/78.21)*x       - we multiply both sides of the equation by x
100=20.20202020202*x       - we divide both sides of the equation by (20.20202020202) to get x
100/20.20202020202=x
4.95=x
x=4.95

now we have:
78.21 is 4.95% of 1580