What is 25 percent of 15.78 - 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 15.78 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 15.78 is 100%, so we can write it down as 15.78=100%.
4. We know, that x is 25% of the output value, so we can write it down as x=25%.
5. Now we have two simple equations:
1) 15.78=100%
2) x=25%
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:
15.78/x=100%/25%
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 25% of 15.78

15.78/x=100/25
(15.78/x)*x=(100/25)*x       - we multiply both sides of the equation by x
15.78=4*x       - we divide both sides of the equation by (4) to get x
15.78/4=x
3.945=x
x=3.945

now we have:
25% of 15.78=3.945