21 is what percent of 2128 - 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 2128 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 2128, so we can write it down as 100%=2128.
4. We know, that x% equals 21 of the output value, so we can write it down as x%=21.
5. Now we have two simple equations:
1) 100%=2128
2) x%=21
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%=2128/21
6. Now we just have to solve the simple equation, and we will get the solution we are looking for.

7. Solution for 21 is what percent of 2128

100%/x%=2128/21
(100/x)*x=(2128/21)*x       - we multiply both sides of the equation by x
100=101.33333333333*x       - we divide both sides of the equation by (101.33333333333) to get x
100/101.33333333333=x
0.98684210526316=x
x=0.98684210526316

now we have:
21 is 0.98684210526316% of 2128