Reasoning and answer: If each shelf has 400 books, then the four shelves have 4 * 400 = 1600 books. Since the total number of books on the shelves is the same as the distance that Karen bikes back home, biking to and from the library takes 1600 + 1600 = 3200 miles.
The answer: 3200
What was the question?
Question: The total number of books on four shelves, with 400 books each, is the same as the distance in miles that Karen bikes back to her home from the library. Calculate the total distance that Karen covers if she bikes from her home to the library and back.


Socorro trains for a total of 10 + 20 = 30 minutes each day. She needs to train for a total of 5 x 60 = 300 minutes since an hour has 60 minutes. Therefore, she will complete her training in 300 / 30 = 10 days.
The answer: 10
Reverse engineering the question: Socorro is preparing for a math contest. She needs to train for a total of 5 hours. Each day, she answers problems about multiplication for 10 minutes and then division problems for 20 minutes. How many days will it take for her to complete her training?


Reasoning and answer: On Monday, Mr Castiel ate 2 / 5 * 600 = 240 sausages. The remaining number of sausages after he ate 240 on Monday is 600 - 240 = 360. On Tuesday, he ate half of the remaining sausages, a total of 360 / 2 = 180. The remaining number of sausages that he saved for Friday after eating 180 on Tuesday is 360 - 180 = 180. On Friday, Mr Castiel ate 3 / 4 * 180 = 135 of the sausages he had kept. The remaining number of sausages after he ate 135 on Friday is 180 - 135 = 45.
The answer: 45
What was the question?
Question: Mr Castiel prepared 600 boar sausages on the weekend. He ate 2/5 of them on Monday, half of the remaining on Tuesday and saved the rest for Friday. If he ate 3/4 of the remaining boar sausages on Friday, how many sausages are left?


First, we need to determine how much the entire meal costs before we can determine the tip. We perform 10 + 20 + 30 = 60 dollars worth of food. Now we need to find out how much the total tip to be paid is, by multiplying 60 * .2 = 12 dollars in tips. Since they want to split this evenly amongst three people, this works out to 12 / 3 = 4 dollars in tips per person.
The answer: 4
Reverse engineering the question: Julie, Letitia and Anton decided to have dinner together at a nearby restaurant. Julie orders $10 worth of food, Letitia orders $20 worth of food, and Anton orders $30 worth of food. How much should each pay in tips if they want to split a 20% tip for the whole meal evenly?


Reasoning and answer: Let "x" be the price of a single necklace. Thus, the cost of the earrings would be 3x. And since all items totaled $240,000, then x + x + x + 3x = $240,000. Therefore, this simplifies to 6x = 240,000. And, solving for x we see that the price of a single necklace is x = $40,000.
The answer: 40000
What was the question?
Question: Princess Daphne bought three necklaces and a set of earrings for a total of $240,000. If all three necklaces were equal in price, and the earrings were three times as expensive as any one necklace, then how expensive was the cost of a single necklace?


Reasoning and answer: From the 9th floor, the elevator went down to the 9 - 7 = 2nd floor. Then went up to the 2 + 3 = 5th floor. Then, went up to the 5 + 8 = 13th floor; hence there are 13 floors in the building.
The answer: 13
What was the question?
Question:
An elevator is on the 9th floor. It goes down 7 floors, then up 3 floors, then up 8 floors. If the elevator is on the top floor, how many floors are there in the building?