The answer is 5400
Step by step:
1. We assume, that the number 18000 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 18000 is 100%, so we can write it down as 18000=100%.
4. We know, that x is 30% of the output value, so we can write it down as x=30%.
5. Now we have two simple equations:
1) 18000=100%
2) x=30%
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:
18000/x=100%/30%
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 30% of 18000
18000/x=100/30
(18000/x)*x=(100/30)*x - we multiply both sides of the equation by x
18000=3.33333333333*x - we divide both sides of the equation by (3.33333333333) to get x
18000/3.33333333333=x
5400=x
x=5400
now we have:
30% of 18000=5400
Hope i have helped