To solve this problem you must apply the proccedure shown below:
1- You have the following information given in the problem: It drops about 5 feet for every 3 feet of horizontal change.
2- Therefore, you have:
Slope=(5 feet/3 feet)x100
Slope=(1.66)x100
Slope=166.66%
Therefore, what is the slope of the first drop?
As you can see, the answer is: 166.66%