We know that Carson takes twice as long as Jerry to get to the school, so we can find the time it takes him by multiplying Jerry's time by 2: 15 minutes * 2 = 30 minutes. Then convert that time to house by dividing by 60 minutes / hour = 30 minutes / 60 minutes / hour = .5 hour. Then divide the distance Carson runs by the time it takes him to run it to find his speed: 4 miles / 0.5 hours = 8 miles / hour.
The answer: 8
Reverse engineering the question: Jerry can run from his house to his school and back in the time it takes his brother Carson to run to the school. If it takes Jerry 15 minutes to make a one-way trip from his house to his school and the school is 4 miles away, how fast does Carson run in miles per hour?
Reasoning and answer: He changed 12 * 2 = 24 motorcycle tires. He changed 10 * 4 = 40 car tires. So he changed 24 + 40 = 64 total tires.
The answer: 64
What was the question?
Question: Mike changes tires on different vehicles. He changes all the tires on 12 motorcycles and all the tires on 10 cars. How many tires did he change?
Shem earns $4 x 2.5 = $10 in an hour. So, Shem earns $10 x 8 = $80 for an 8 - hour workday.
The answer: 80
Reverse engineering the question: Shem makes 2.5 times more money per hour than Kem. If Kem earns $4 per hour, how much does Shem earn for an 8-hour workday?
Reasoning and answer: There are 200 + 32 = 232 red apples. After the delivery there are 340 + 32 = 372 green apples. There are now 372 - 232 = 140 more green apples than red apples now.
The answer: 140
What was the question?
Question: There are 200 more red apples than green apples in a grocery store. A truck arrives and delivers another 340 green apples. If there were originally 32 green apples, how many more green apples than red apples are there in the store now?
The old team per round record is 1,148 because 287 x 4 = 1,148. The team season record is 11,480 because 10 x 1,248 = 11,480. They need 1,040 points in the final round to tie the record because 11,480 - 10,440 = 1,040. They need to average 260 points each because 1,040 / 4 = 260. This is 27 points less than the current record average because 287 - 260 = 27.
The answer: 27
Reverse engineering the question: George's bowling team is one round away from breaking the league record for most points scored in a season. The old record is an average score per player of 287 per round. Each team has 4 players and there are 10 rounds in the season. Through the first 9 rounds, his team has scored a total of 10,440. How many points less than the current league record per game average is the minimum average they need to score, per player, in the final round to tie the league record?
Each day it needs to consume 7 / 7 = 1 gallon of blood. There are 128 / 16 = 8 pints per gallon. So he needs to suck blood from 8 / 2 = 4 people per day.
The answer: 4
Reverse engineering the question:
A vampire needs to suck 7 gallons of blood per week to survive. If he sucks 2 pints of blood per person, how many people does he need to suck each day to survive?