55 is what 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 100% equals 399, so we can write it down as 100%=399.
4. We know, that x% equals 55 of the output value, so we can write it down as x%=55.
5. Now we have two simple equations:
1) 100%=399
2) x%=55
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:
100%/x%=399/55
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 55 is what percent of 399

100%/x%=399/55
(100/x)*x=(399/55)*x       - we multiply both sides of the equation by x
100=7.2545454545455*x       - we divide both sides of the equation by (7.2545454545455) to get x
100/7.2545454545455=x
13.784461152882=x
x=13.784461152882

now we have:
55 is 13.784461152882% of 399