Answer:
 Women comprise between 16.7% and 18.2% of top earners.
Step-by-step explanation:
You want the percent of top earners in the US who are women if the number of top earners who are men is 4.5 to 5 times the number who are women.
Let w represent the fraction of top earners who are women. Then (1-w) is the fraction who are men. The problem statement tells us ...
 4.5 < (1 -w)/w < 5
Multiplying by 5 gives ...
 4.5w < 1 -w < 5w
Adding w, we have ...
 5.5w < 1 < 6w
Solving each of these inequalities for w gives ...
 5.5w < 1  ⇒  w < 1/5.5 ≈ 18.2%
 1 < 6w  ⇒  w > 1/6 ≈ 16.7%
The percent of top earners in the US who are women se more than 16.7% and less than 18.2%.