To get the solution, we are looking for, we need to point out what we know.

1. We assume, that the number 64 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 64, so we can write it down as 100%=64.

4. We know, that x% equals 16 of the output value, so we can write it down as x%=16.

5. Now we have two simple equations:

1) 100%=64

2) x%=16

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%=64/16

6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 16 is what percent of 64

100%/x%=64/16

(100/x)*x=(64/16)*x - we multiply both sides of the equation by x

100=4*x - we divide both sides of the equation by (4) to get x

100/4=x

25=x

x=25

now we have:

16 is 25% of 64

16 / 64 is the same as 1/4 because 16 is 1/4 of 64.

1/4 in percent form is 25%

So, 16 is 25% of 64.