What is 405 percent of 18 - 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 18 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 18 is 100%, so we can write it down as 18=100%.
4. We know, that x is 405% of the output value, so we can write it down as x=405%.
5. Now we have two simple equations:
1) 18=100%
2) x=405%
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:
18/x=100%/405%
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 405% of 18

18/x=100/405
(18/x)*x=(100/405)*x       - we multiply both sides of the equation by x
18=0.24691358024691*x       - we divide both sides of the equation by (0.24691358024691) to get x
18/0.24691358024691=x
72.9=x
x=72.9

now we have:
405% of 18=72.9