The grill burned 3 * 60 = 180 coals. It takes 20 minutes to burn 15 coals, so the grill ran for 180 / 15 * 20 = 240 minutes.
The answer: 240
Reverse engineering the question: A charcoal grill burns fifteen coals to ash every twenty minutes of grilling. The grill ran for long enough to burn three bags of coals. Each bag of coal contains 60 coals. How long did the grill run?


Reasoning and answer: According to the ratio, for every 5 parts that Johnson gets, Mike gets 2 parts. Since Johnson got $2500, each part is therefore $2500 / 5 = $500. Mike will get 2 * $500 = $1000. After buying the shirt he will have $1000 - $200 = $800 left.
The answer: 800
What was the question?
Question: The profit from a business transaction is shared among 2 business partners, Mike and Johnson in the ratio 2:5 respectively. If Johnson got $2500, how much will Mike have after spending some of his share on a shirt that costs $200?


First find the number of cups of banana mush Hannah gets: 20 bananas / 4 bananas / cup = 5 cups. Then multiply the number of cups of mush by the ratio of flour to mush to find the number of cups of flour: 5 cups mush * 3 cups flour / 1 cup mush = 15 cups flour.
The answer: 15
Reverse engineering the question: Hannah is making banana bread. She needs to use 3 cups of flour for every cup of banana mush. It takes 4 bananas to make one cup of mush. If Hannah uses 20 bananas, how many cups of flour should she use?


Reasoning and answer: Let B be the number of apples that Buffy stole. Then 79 - B - 26 = 8. Combining constants produces 53 - B = 8. Adding B to both sides produces 52 = B + 8. Thus the number of apples stolen by Buffy is B = 53 - 8 = 45.
The answer: 45
What was the question?
Question: Every morning, Carla puts 79 apples in her backpack to eat for lunch. Unfortunately, Buffy stole some of Carla's apples on the school bus, and 26 apples fell out of a hole on the bottom. So at lunchtime, Carla only had 8 apples remaining. How many apples did Buffy steal from Carla?


Let x represent the number of miles Kati drives. Michelle:3x. Tracy:20 + 2(3x) = 20 + 6x. Total:x + 3x + 20 + 6x = 1000. 10x + 20 = 1000. 10x = 980. x = 98 miles. 3(98) = 294 miles.
The answer: 294
Reverse engineering the question: Tracy, Michelle, and Kati take a road trip that is a total of 1000 miles. Tracy drives 20 miles more than twice Michelle, and Michelle drives 3 times the amount that Katie drives. How many miles does Michelle drive?


The number of non - valuable files Brennan downloaded in the first round is 70 / 100 * 800 = 560 files. The number of valuable files Brennan downloaded in the first round is 800 - 560 = 240. When he downloaded 400 new files, there were 3 / 5 * 400 = 240 non - useful files, which he deleted again. The total number of valuable files he downloaded in the second round is 400 - 240 = 160. To write his research, Brennan had 160 + 240 = 400 useful files to reference to write his research.
The answer: 400
Reverse engineering the question:
Brennan was researching his school project and had to download files from the internet to his computer to use for reference. After downloading 800 files, he deleted 70% of them because they were not helpful. He downloaded 400 more files but again realized that 3/5 of them were irrelevant. How many valuable files was he left with after deleting the unrelated files he downloaded in the second round?