Answer:
15%
Step-by-step explanation:
We assume, that the number 9400 is 100% - because it's the output value of the task.
x is the value we are looking for.
If 100% equals 9400, so we can write it down as 100%=9400.
We know, that x% equals 7990 of the output value, so we can write it down as x%=7990.
Now we have two simple equations:
100%=9400
x%=7990
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%=9400/7990
Now we just have to solve the simple equation, and we will get the solution we are looking for.
Solution for 7990 is what percent of 9400.