To get the solution, we are looking for, we need to point out what we know.
1. We assume, that the number 81 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 81 is 100%, so we can write it down as 81=100%.
4. We know, that x is 63% of the output value, so we can write it down as x=63%.
5. Now we have two simple equations:
1) 81=100%
2) x=63%
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:
81/x=100%/63%
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 63% of 81
81/x=100/63
(81/x)*x=(100/63)*x - we multiply both sides of the equation by x
81=1.5873015873*x - we divide both sides of the equation by (1.5873015873) to get x
81/1.5873015873=x
51.03=x
x=51.03
now we have:
63% of 81=51.03
