Q: Peter and Kristin are to read 20 fantasy novels each in a week. Peter can read three times as fast as Kristin. If Peter reads one book in 18 hours, how long will Kristin read half of her books?
A: Since Peter reads three times as fast as Kristin, Kristin will take 18 * 3 = 54 hours to read one book. Kristin reads half of her books, a total of 20 / 2 = 10 books. The time Kristin will take to read half of her books is 10 * 54 = 540. The answer is 540.

Q: Drew is reseeding his lawn with grass seed. One bag of grass seed covers 250 square feet of lawn. His lawn is 22 feet from the house to the curb and 36 feet from side to side. He bought four bags of seed. How many extra square feet could the leftover grass seed cover after Drew reseeds his lawn?
A: Drew's lawn is 22 * 36 = 792 square feet. He bought enough grass seed to cover 250 * 4 = 1000 square feet. Thus, the leftover grass seed can cover 1000 - 792 = 208 square feet. The answer is 208.

Q: Wickham is throwing a huge Christmas party. He invites 30 people. Everyone attends the party, and half of the guests bring a plus one (one other person). He plans to serve a 3-course meal for the guests. If he uses a new plate for every course, how many plates does he need in total for his guests?
A:
The number of guests that bring a plus one is 30 / 2 = 15 guests. The total number of guests at the party, including the plus ones, is 30 + 15 = 45 guests. Since there are 3 courses, Wickham will need 45 * 3 = 135 plates. The answer is 135.