Answer:
4/7 or 57.14% in percentage form
Step-by-step explanation:
If a package in that weight class can be any weight between 14-20lb then there are a total of 7 different possible weights. Out of all of these only 4 are actually less than 18lbs, those weights are 14, 15, 16, 17. Therefore, since weights are evenly distributed in that weight class then the possibility of a package being less than 18lbs would be
4/7 or 0.5714 or 57.14%