1. We assume, that the number 45 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 45 is 100%, so we can write it down as 45=100%.
4. We know, that x is 80% of the output value, so we can write it down as x=80%.
5. Now we have two simple equations:
1) 45=100%
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:
45/x=100%/80%
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 80% of 45
45/x=100/80
(45/x)*x=(100/80)*x - we multiply both sides of the equation by x
45=1.25*x - we divide both sides of the equation by (1.25) to get x
45/1.25=x
36=x
x=36
now we have:
80% of 45=36
I HOPE THIS HELPS
