What is 0.3 percent of 4200 - 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 4200 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 4200 is 100%, so we can write it down as 4200=100%.
4. We know, that x is 0.3% of the output value, so we can write it down as x=0.3%.
5. Now we have two simple equations:
1) 4200=100%
2) x=0.3%
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:
4200/x=100%/0.3%
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 0.3% of 4200

4200/x=100/0.3
(4200/x)*x=(100/0.3)*x       - we multiply both sides of the equation by x
4200=333.333333333*x       - we divide both sides of the equation by (333.333333333) to get x
4200/333.333333333=x
12.6=x
x=12.6

now we have:
0.3% of 4200=12.6