The total expenses are $140 + $43 + $15 = $198. Mr. Doré paid $200, so the saleswoman must give him $200 - $198 = $2 back.
The answer: 2
Reverse engineering the question: Mr. Doré bought $140 worth of pants, a $43 shirt and a $15 tie. He pays with a $200 bill. How much will the saleswoman give him back?

After giving away four of her cats, Susan has 21 - 4 = 17. Susan has 17 - 3 = 14 more cats than Bob.
The answer: 14
Reverse engineering the question: Susan has 21 cats and Bob has 3 cats. If Susan gives Robert 4 of her cats, how many more cats does Susan have than Bob?

Verna weighs 103 + 17 = 120 pounds. Sherry weighs 120 * 2 = 240 pounds. Verna and Sherry weigh 120 + 240 = 360 pounds together.
The answer: 360
Reverse engineering the question: Verna weighs 17 pounds more than Haley, and Verna weighs half as much as Sherry. If Haley weighs 103 pounds, how many pounds do Verna and Sherry weigh together?

Half as many legs as a single spider has is 8 / 2 = 4 legs. 10 more spiders than half as many legs as a single spider has is 4 + 10 = 14 spiders. The total number of spider legs in a group of 14 spiders is 8 * 14 = 112 spider legs.
The answer: 112
Reverse engineering the question:
A spider has eight legs. If a group of spiders has 10 more spiders than half as many legs as a single spider has, what is the total number of spider legs in this group of spiders?