15 is what percent of 258 - 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 258 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 258, so we can write it down as 100%=258.
4. We know, that x% equals 15 of the output value, so we can write it down as x%=15.
5. Now we have two simple equations:
1) 100%=258
2) x%=15
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%=258/15
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 15 is what percent of 258

100%/x%=258/15
(100/x)*x=(258/15)*x       - we multiply both sides of the equation by x
100=17.2*x       - we divide both sides of the equation by (17.2) to get x
100/17.2=x
5.8139534883721=x
x=5.8139534883721

now we have:
15 is 5.8139534883721% of 258