[Question]Andrea needs 45 rhinestones to finish an art project. She bought a third of what she needed and found a fifth of what she needed in her supplies. How many rhinestones does she still need?
[Answer]Andrea bought 45 / 3 = 15 rhinestones. She found 45 / 5 = 9 rhinestones in her supplies. Thus, Andrea still needs 45 - 15 - 9 = 21 rhinestones. The answer is 21.
Q: In a batch of 30 apples, 1/6 are too small and 1/3 are not ripe. The others are perfect. Calculate the number of perfect apples.
A: We first calculate the proportion of all the other apples: 1 / 6 + 1 / 4 + 1 / 12 = 2 / 12 + 3 / 12 + 1 / 12 = 6 / 12. So, the proportion of perfect apples is 12 / 12 - 6 / 12 = 6 / 12 = 0.5. Thus the number of perfect apples is 0.5 * 30 = 15. The answer is 15.
Question: Josh has a device that automatically records the temperature in his lab every 5 seconds. To perform an analysis of environmental conditions, Josh lets the device record data for one hour. How many instances of data will the device record?
Answer: There are 60 minutes in an hour, and 60 seconds in a minute so there are 60 * 60 = 3600 seconds in an hour. The device records data every 5 seconds so there will be 3600 / 5 = 720 instances of data in an hour. The answer is 720.
[Question]A pack of dogs found a pile of bones in the dumpster behind the butcher shop. One by one, the dogs crawled into the dumpster, grabbed a mouthful of bones, and ran off with their newfound treasure. In all, there were 5 dogs. The first dog carried off 3 bones. The second dog carried off 1 less bone than the first dog. The third dog carried off twice as many as the second dog. The fourth dog carried off one bone, and the fifth dog carried off twice the number of bones as the fourth dog carried, leaving no remaining bones in the dumpster. How many bones were in the original pile of bones?
[Answer]The second dog carried off 1 less bone than the first dog, or 3 - 1 = 2 bones. The third dog carried off twice as many bones as the third dog, or 2 * 2 = 4 bones. The fifth dog carried off twice the number of bones as the fourth dog carried, or 2 * 1 = 2 bones. Therefore, the original pile of bones contained 3 + 2 + 4 + 1 + 2 = 12 bones. The answer is 12.
Q: Matt can make a batch of a dozen cookies using 2 pounds of flour. He uses 4 bags of flour each weighing 5 pounds. If Jim eats 15 cookies how many cookies are left?
A: Matt used 4 * 5 = 20 pounds of flour. That means he made 20 / 2 = 10 batches. So he cooked 10 * 12 = 120 cookies. After Jim eats 15 there are 120 - 15 = 105 cookies left. The answer is 105.
Question: Bertha plays tennis. Every ten games, one of her tennis balls wears out. Every five games, she loses a ball. Every four games, she buys a canister of three balls. She started with two balls and gave one to her partner. After twenty games, how many tennis balls does she have?
Answer:
Bertha wears out 20 / 10 = 2 tennis balls in 20 games. She loses 20 / 5 = 4 tennis balls in 20 games. She buys canisters of 3 * 20 / 4 = 15 tennis balls in 20 games. Bertha started with 2 balls and gave 1 away, so she has 2 + 15 - 2 - 4 - 1 = 10 tennis balls after twenty games. The answer is 10.