What is 70 percent of 21990 - 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 21990 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 21990 is 100%, so we can write it down as 21990=100%.
4. We know, that x is 70% of the output value, so we can write it down as x=70%.
5. Now we have two simple equations:
1) 21990=100%
2) x=70%
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:
21990/x=100%/70%
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 70% of 21990

21990/x=100/70
(21990/x)*x=(100/70)*x       - we multiply both sides of the equation by x
21990=1.4285714285714*x       - we divide both sides of the equation by (1.4285714285714) to get x
21990/1.4285714285714=x
15393=x
x=15393

now we have:
70% of 21990=15393