Q: Justice has 3 ferns, 5 palms, and 7 succulent plants in her house. If she wants a total of 24 plants in her home, how many more plants does she need?
A: Justice currently has 3 + 5 + 7 = 15 plants in her house. Justice needs 24 - 15 = 9 more plants. The answer is 9.

Q: Dr. Harry wants to know how many candies Susan consumed during the week. Susan tells him she bought 3 on Tuesday, 5 on Thursday, 2 on Friday. If she has only 4 of them left, how many did she eat?
A: She had bought 3 + 5 + 2 = 10 candies over the week. She has only 4 left which means she ate 10 - 4 = 6 candies during the week. The answer is 6.

Q: Melody has three dogs. Each dog eats 1/2 of a pound of dog food twice a day. If Melody bought 30 pounds of dog food, how many pounds of dog food are left after a week?
A:
Each dog eats 1 / 2 x 2 = 1 pound of dog food each day. So the three dogs eat a total of 1 x 3 = 3 pounds each day. That is 3 x 7 = 21 pounds in a week. Therefore, 30 - 21 = 9 pounds of food are left after a week. The answer is 9.