The time it took Manu to complete the race is 60 + 12 = 72 seconds. If Amy is twice as fast as Manu, then she takes half the time Manu did to finish the race, so Amy took 1 / 2 * 72 = 36 seconds.
The answer: 36
Reverse engineering the question: When Patrick, Manu, and Amy participate in a race they realize that Patrick finishes the race in 60 seconds. Manu took 12 more seconds to finish the race. If Amy is twice as fast as Manu, how long did it take her to finish the race?


Reasoning and answer: Dale's batch needs to be 35 ÷ 7 = 5 times larger than the original recipe. Dale needs 2 × 5 = 10 pounds of pasta.
The answer: 10
What was the question?
Question: Dale just learned how to make homemade macaroni and cheese. He decided to make a big batch for his family reunion. The original recipe calls for 2 pounds of pasta and serves 7 people. Dale's family reunion will have 35 people. How many pounds of pasta does Dale need to buy?


Ed spent $1.50 x 6 = $9 for staying in the hotel last night. He spent $2 x 4 = $8 for staying in the hotel this morning. So, the total money he spent in the hotel is $9 + $8 = $17. Therefore, he still has $80 - $17 = $63 left after staying in the hotel.
The answer: 63
Reverse engineering the question: Ed booked a hotel while he was on vacation. Staying at the hotel cost was $1.50 per hour every night and $2 per hour every morning. If Ed had $80 and he stayed in the hotel for 6 hours last night and 4 hours this morning, how much money was he left with after paying for his stay at the hotel?


Reasoning and answer: The number of rolls already sold is 1 + 10 + 6 = 17. Nellie needs to sell 45 − 17 = 28 more rolls of gift wrap.
The answer: 28
What was the question?
Question: For a fundraiser, Nellie needs to sell 45 rolls of gift wrap. So far, she has sold 1 roll to her grandmother, 10 rolls to her uncle, and 6 rolls to a neighbor. How many more rolls of gift wrap does Nellie need to sell?


First convert the length of the first video to seconds: 2 minutes * 60 seconds / minute = 120 seconds. Then convert the length of the second video to seconds: 4 minutes * 60 seconds / minute + 30 seconds = 240 seconds + 30 seconds = 270 seconds. Now subtract the length of the first two videos from the total time Kimiko spent watching to find the combined length of the last two videos: 510 seconds - 120 seconds - 270 seconds = 120 seconds. Now divide the combined length by the number of videos to find each video's length: 120 seconds / 2 = 60 seconds.
The answer: 60
Reverse engineering the question: Kimiko watches four YouTube videos. The first video is 2 minutes long, the second video is 4 minutes and 30 seconds, and the last two videos are equal in length. If she spends a total of 510 seconds watching YouTube, how many seconds long was each of the last two videos?


Halfway towards her goal is $45 because 90 / 2 = 45. She sells $35 worth of books before she loses the money because 45 - 10 = 35. She sells 7 books before losing her money because 35 / 7 = 5. She then sells 18 books because 90 / 5 = 18. She sells 25 books in total because 18 + 7 = 25.
The answer: 25
Reverse engineering the question:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
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Tara is saving up to buy a new clarinet. She already has $10 saved. The clarinet costs $90. She plans to sell her old books to make the money. She sells each book of hers for $5. However, when she is halfway towards her goal, she loses all her savings and has to start over. How many books does she sell in total by the time she reaches her goal?