What is 45 percent of 172.8 - 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 172.8 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 172.8 is 100%, so we can write it down as 172.8=100%.
4. We know, that x is 45% of the output value, so we can write it down as x=45%.
5. Now we have two simple equations:
1) 172.8=100%
2) x=45%
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:
172.8/x=100%/45%
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for what is 45% of 172.8

172.8/x=100/45
(172.8/x)*x=(100/45)*x       - we multiply both sides of the equation by x
172.8=2.2222222222222*x       - we divide both sides of the equation by (2.2222222222222) to get x
172.8/2.2222222222222=x
77.76=x
x=77.76

now we have:
45% of 172.8=77.76