Reasoning and answer: Let S be the length of the short side of the fence. Thus, the length of a long side of the fence is 3S. There are 2 of each side, so the whole fence is 2S + 2 * 3S = 2S + 6S = 8S long. The whole fence is 8S = 640 feet long. Thus, the short side of the fence that needs to be replaced is S = 640 / 8 = 80 feet long.
The answer: 80
What was the question?
Question: A rectangular plot of private property is fenced in by a chain-link fence. The long sides of the plot are three times the length of the short sides. One short side of the fence is rusted from being hit by a sprinkler and needs to be replaced. If all the sides of the fence together are 640 feet long, how many feet of fence need to be replaced?


In a week, working 10 hours a day, Bob logs 10 * 5 = 50 hours. After a month with 4 weeks, Bob logs 4 * 50 = 200 hours for his office working hours.
The answer: 200
Reverse engineering the question: Every day, Bob logs 10 hours of work in his office. If he works for five days a week, calculate the total number of hours he logs in a month.


Reasoning and answer: First figure out how many minutes Carson spends at the carnival by multiplying the number of hours he's there by the number of minutes per hour: 4 hours * 60 minutes / hour = 240 minutes. Then figure out how long Carson spends waiting for the roller coaster by multiplying the wait time per ride by the number of rides: 4 rides * 30 minutes / ride = 120 minutes. Now subtract the time Carson spends on the roller coaster and tilt - a - whirl from the total time he spends at the park to find out how much time he has left: 240 minutes - 120 minutes - 60 minutes = 60 minutes. Now divide the time Carson has left by the wait time for the giant slide to see how many times he can ride it: 60 minutes / 15 minutes / ride = 4 rides.
The answer: 4
What was the question?
Question: Carson is going to spend 4 hours at a carnival. The wait for the roller coaster is 30 minutes, the wait for the tilt-a-whirl is 60 minutes, and the wait for the giant slide is 15 minutes. If Carson rides the roller coaster 4 times and the tilt-a-whirl once, how many times can he ride the giant slide? (Wait times include the time actually spent on the ride.)


The cost of the 200 employees is 200 employees * $12 / employee / hour = $2400 per hour. The cost of the 40 employees is 40 employees * $14 / employee / hour = $560 per hour. The rest means 300 employees - 200 employees - 40 employees = 60 employees. These 60 employees' employment costs are at 60 employees * $17 / employee / hour = $1020 per hour. So in total all employees earn $2400 / hour + $560 / hour + $1020 / hour = $3980 / hour. During an 8 - hour shift, this cost would be at 8 hours * $3980 / hour = $31840.
The answer: 31840
Reverse engineering the question: In a factory, there are 300 employees. 200 of them earn $12 per hour. Of the rest, 40 of them earn $14 per hour. All others earn $17 per hour. What is the cost to employ all these people for one 8-hour long shift?


Reasoning and answer: 40 / 4 = 10 kids went tubing. 10 / 2 = 5 kids went rafting and tubing.
The answer: 5
What was the question?
Question: There were 40 kids on Lake Pleasant. A fourth of the kids went tubing, but only half of the tubers went rafting. How many of the kids who joined the rafting excursion were also on the tubing excursion?


Reasoning and answer: Sonja uses 2 ounces of oil for 8 ounces of peanuts to make 2 + 8 = 10 ounces of peanut butter. Her last batch weighed 20 ounces, so she made 20 / 10 = 2 times her ratio. Thus, she used 2 * 2 = 4 ounces of oil.
The answer: 4
What was the question?
Question:
Sonja makes her own peanut butter with peanuts and oil in a blender. She uses a ratio of two ounces of oil to smooth out every eight ounces of peanuts. Her last batch of peanut butter weighed 20 ounces. How many ounces of oil did she use?