What is 13 percent of 399 - 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 399 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 399 is 100%, so we can write it down as 399=100%.
4. We know, that x is 13% of the output value, so we can write it down as x=13%.
5. Now we have two simple equations:
1) 399=100%
2) x=13%
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:
399/x=100%/13%
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 13% of 399

399/x=100/13
(399/x)*x=(100/13)*x       - we multiply both sides of the equation by x
399=7.6923076923077*x       - we divide both sides of the equation by (7.6923076923077) to get x
399/7.6923076923077=x
51.87=x
x=51.87

now we have:
13% of 399=51.87