6.4 is what percent of 5 - 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 5 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 5, so we can write it down as 100%=5.
4. We know, that x% equals 6.4 of the output value, so we can write it down as x%=6.4.
5. Now we have two simple equations:
1) 100%=5
2) x%=6.4
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%=5/6.4
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 6.4 is what percent of 5

100%/x%=5/6.4
(100/x)*x=(5/6.4)*x       - we multiply both sides of the equation by x
100=0.78125*x       - we divide both sides of the equation by (0.78125) to get x
100/0.78125=x
128=x
x=128

now we have:
6.4 is 128% of 5