First find the number of minutes in 2 hours: 2 hours * 60 minutes / hour = 120 minutes. Then add 10 minutes to that amount to find the total number of minutes Walter spent at the zoo: 120 minutes + 10 minutes = 130 minutes. Let s be the amount of time he spends looking at the seals and p be the amount of time he spends looking at the penguins. From the problem, we know that s + p + 13 = 130 and p = 8s. Substituting the second equation into the first, we get s + 8s + 13 = 130. Combining like terms, we get 9s + 13 = 130. Subtracting 8 from both sides, we get 9s = 117. Dividing both sides by 9, we get s = 13.
The answer: 13
Reverse engineering the question: Walter goes to the zoo, where he spends a certain amount of time looking at the seals, eight times as long looking at the penguins, and 13 minutes looking at the elephants. If he spent 2 hours and 10 minutes at the zoo, how many minutes did he spent looking at the seals?
Reasoning and answer: If Calen lost 10 pencils, which left him with 10 pencils, then Calen originally had 10 + 10 = 20 pencils. Calen originally had 5 more pencils than does Caleb, and thus Caleb has 20 - 5 = 15 pencils. Let's let "x" represent the number of pencils owned by Candy. Since Caleb has 3 less than twice as many pencils as does Candy, then (2 * x) - 3 = 15. This simplifies to 2 * x = 18. Thus, the number of pencils owned by Candy is x = 9 pencils.
The answer: 9
What was the question?
Question: Calen originally had 5 more pencils than does Caleb, and Caleb has 3 less than twice as many pencils as does Candy. If Calen lost 10 pencils, which left him with 10 pencils, then how many pencils does Candy have?
The shadow of Jane is 1.5 / 0.5 = 3 times smaller than her height. The height of the tree is therefore 3 times bigger than the shadow, so it's 3 * 10 = 30 meters tall.
The answer: 30
Reverse engineering the question: Jane is looking at a tree. At the same time, the tree and Jane are casting shadows - the tree of 10 meters and Jane of 0.5 meters. Jane is 1.5 meters tall. How tall is the tree?
Reasoning and answer: Let d be the number of drunk drivers and s be the number of speeders. We know that d + s = 45 and s = 7d - 3. Substituting the second equation into the first equation, we get d + 7d - 3 = 45. Combining like terms, we get 8d - 3 = 45. Adding 4 to both sides, we get 8d = 48. Dividing both sides by 8, we get d = 6.
The answer: 6
What was the question?
Question: In a court-mandated traffic class, there are a certain number of drunk drivers and 3 less than 7 times that many speeders. If there are 45 students total, how many drunk drivers are there?
She mowed lawns for 25 hours in September, so earned 25 * $4 = $100. She pulled weeds for 3 hours in September, so earned 3 * $8 = $24. She earned $100 + $24 = $124 in September. Finally, for two months working the same hours she earned $124 * 2 = $248.
The answer: 248
Reverse engineering the question: Julie started her own landscaping business. She charges $4 an hour for mowing lawns and $8 for pulling weeds. In September she mowed lawns for 25 hours and pulled weeds for 3 hours. If she worked the same number of hours in October, how much money did she earn in September and October?
A total of 4 + 6 = 10 cars are in the shop throughout the week. This means the shop buys 10 cars * 4 tires = 40 tires. For each of the customers that only want half the tires changing, there are 4 tires * 0.5 = 2 tires left over. Two of the customers only want half the tires changing, so there are 2 tires * 2 cars = 4 tires left over from these customers. Out of the remaining tires, there are 20 4 = 16 tires left from customers who don't want their tires changing. So in total, there were 16 tires / 4 tires per customer = 4 customers who did not want their tires changing.
The answer: 4
Reverse engineering the question:
An auto shop buys tires to replace all the tires on every customer's car. They buy the tires as soon as cars are brought into the shop. There are four cars in the shop already, and another six customers come into the shop throughout the week. Some of the customers decide they don't want any of the tires changing, and two customers decide they only want half the tires changing. They had no tires in stock at the start of the week. If the shop has 20 tires left at the end of the week, how many customers decided they did not want their tires changing?