25% of oysters have pearls in them. Jamie can collect 16 oysters during each dive. How many dives does he have to make to collect 56 pearls? Give the rationale and then the answer.
Let's think step by step. First find how many pearls Jamie collects per dive by multiplying the number of oysters by the chance each oyster has a pearl: .25 pearls / oyster * 16 oysters / dive = 4 pearls / dive. Then divide the number of pearls he wants by the number of pearls per dive to find the number of dives: 56 pearls / 4 pearls / dive = 14 pearls / dive.. The answer is: 14.

Miss Molly surveyed her class of 30 students about their favorite color. Half of the class answered green, one-third of the girls answered pink, and the rest of the class answered yellow. If there are 18 girls in the class, how many students like yellow best? Give the rationale and then the answer.
Let's think step by step. 30 / 2 = 15 students answered green. 18 / 3 = 6 girls answered pink. So, 15 + 6 = 21 students answered either green or pink. Therefore, 30 - 21 = 9 answered yellow.. The answer is: 9.

Shawna's workout goal is 30 situps. On Monday, Shawna was only able to do 12 situps, so she decided that she would make up for the rest on Tuesday. However, she was only able to do 19 situps on Tuesday. How many situps would Shawna have to do on Wednesday to meet her minimum goal and make up for the ones she didn't do? Give the rationale and then the answer.
Let's think step by step. On Monday, Shawna was short of 30 - 12 = 18 situps. On Tuesday, Shawna was short of 30 - 19 = 11 situps. On Wednesday, Shawna would have to do 30 + 18 + 11 = 59 situps.. The answer is: 59.