Q: John drives 1000 miles a month. He needs to get an oil change every 3000 miles. He gets 1 free oil change a year. If an oil change costs $50, how much does he pay a year?
A: He needs to get an oil change every 3000 / 1000 = 3 months. So he gets 12 / 3 = 4 oil changes a year. That means he pays for 4 - 1 = 3 oil changes a year. So he pays 3 * $50 = $150 a year. The answer is 150.
Question: There are 20 dolphins in the aqua park. One-fourth of the dolphins are fully trained. Two-third of the remaining dolphins are currently in training and the rest will be trained next month. How many dolphins will be trained next month?
Answer: 20 x 1 / 4 = 5 dolphins are fully trained. So, 20 - 5 = 15 dolphins are not yet fully trained. 15 x 2 / 3 = 10 are currently in training. Therefore, 15 - 10 = 5 dolphins will be trained next month. The answer is 5.
[Question]Paul's grades last semester were very bad. To encourage him, Paul's dad promised him $5 for every B+ he gets in his next scorecard and twice that amount for every A. If Paul obtains at least two A+ he'll double the previous rewards and would receive a flat $15 for every A+ obtained (with no extra bonus). If there are 10 courses with grades in Paul's scorecard, what's the maximum amount he could receive from his dad?
[Answer]We know Paul would get $5 for a B + . However, we know this could be (2x) doubled if he obtains at least two A + . This means 2 * $5 = $10 for a B + if Paul gets at least two A + . We know Paul would get twice the reward of a B + if he gets an A. This means 2 * $5 = $10 for every A. However, we know his reward for every A could be (2x) doubled if he obtains at least two A + . This means 2 * $10 = $20 for every A if Paul gets at least two A + . We learn here then that Paul will get a higher reward for obtaining A grades ($20) than getting A + grades ($15) as long as he's able to score at least two A + . To maximize his payout, Paul will need to get only (2) two A + from his 10 courses. Therefore he should aim to get an A in the remaining 10 - 2 = 8 courses. Assuming Paul can get two A + and eight A in his next scorecard his total payout would be 2 * $15 + 8 * $20. This translates into $30 + $160 or $190. The answer is 190.
Q: In Grade 4, there are two sections -- Diligence and Industry. The two sections have an equal number of students after 2 students were transferred from section Industry to Diligence. How many students were there in section Diligence before the transfer if, in both sections combined, there are a total of 50 students?
A: There are 50 / 2 = 25 students in each section now. So, there were 25 - 2 = 23 students in section Diligence before 2 students were transferred in their section. The answer is 23.
Question: For the family reunion, Peter is buying 16 pounds of bone-in chicken and half that amount in hamburgers. He's going to buy 2 more pounds of hot dogs than hamburgers. He's also going to buy several sides that will weigh half the amount of hot dogs. How many pounds of food will he buy?
Answer: He is buying 16 pounds of chicken and half that amount in hamburgers so he's buying 16 / 2 = 8 pounds of hamburgers. He's going to buy 2 more pounds of hotdogs than hamburgers, which are 8 pounds so he'll have 2 + 8 = 10 pounds of hot dogs. He's going to buy sides that weigh half the amount of the hot dogs so that's 10 / 2 = 5 pounds of sides. He's buying 16 pounds of chicken, 8 pounds of hamburgers, 10 pounds of hot dogs and 5 pounds of sides for a total of 16 + 8 + 10 + 5 = 39 pounds of food. The answer is 39.
Q: Aida has twice as many dolls as Sophie, and Sophie has twice as many dolls as Vera. How many dolls do Aida, Sophie, and Vera have combined if Vera has 20 dolls?
A:
If Sophie has twice as many dolls as Vera, then she has 2 * 20 dolls = 40 dolls. Aida has 2 * 40 dolls = 80 dolls, twice the number Sophie has. In total, they have 80 dolls + 40 dolls + 20 dolls = 140 dolls. The answer is 140.