If Each of the roads has 250 street lights on each opposite side, the total number of street lights on one road is 250 * 2 = 500. Since each neighborhood has four roads passing through it, the total number of street lights in one neighborhood is 500 * 4 = 2000 street lights. The town has ten neighborhoods, and since each neighborhood has 2000 street lights on all its roads, there are 2000 * 10 = 20000 street lights in the town.
The answer: 20000
Reverse engineering the question: A town has ten neighborhoods, each having four roads passing through them. Each of the roads has 250 street lights on each opposite side. Calculate the total number of street lights on all the roads of the neighborhoods in the town.


Reasoning and answer: If she had 400 papers, the total number of documents she separated as invalid is 40 / 100 * 400 pages = 160 pages. The number of valid documents is 400 pages - 160 pages = 240 pages.
The answer: 240
What was the question?
Question: Cameron is printing her thesis in the school library and has 400 A4 pieces of paper. If 40% of the papers did not print out up to her desired quality and she separated them as invalid, calculate the total number of valid documents.


The computer and printer cost 400 + 40 = 440 dollars. Delores has 450 - 440 = 10 dollars left.
The answer: 10
Reverse engineering the question: Delores has $450. She buys a computer for $400 and a printer for $40. How much money, in dollars, does Delores have left?


Reasoning and answer: Jill bought 5 packs * 18 red balls = 90 red balls. Jill bought 4 packs * 18 yellow balls = 72 red balls. Jill had 90 red – 72 yellow = 18 more red balls.
The answer: 18
What was the question?
Question: Jill bought 5 packs of red bouncy balls and 4 packs of yellow bouncy balls. Each package contained 18 bouncy balls. How many more red bouncy balls than yellow bouncy balls did Jill buy?


First find the height of the bone meal plant: 36 inches * 125% = 45 inches. Then find the height of the cow manure plant: 45 inches * 200% = 90 inches.
The answer: 90
Reverse engineering the question: Jenny wants to know whether bone meal or cow manure makes better fertilizer. The control plant with no fertilizer grows 36 inches high, the plant with bone meal grows to 125% of the height of the control plant, and the cow manure plant grows to 200% of the height of the bone meal plant. How tall is the cow manure plant in inches?


Michonne has invited 6 + 12 = 18 friends. These friends have invited another 18 friends * 2 = 36 people. So in total, there are 18 friends + 36 people = 54 people going to Michonne’s party.
The answer: 54
Reverse engineering the question:
Michonne is inviting her friends to her birthday party. She invites 6 of her friends from school and 12 of her friends from her neighborhood. Each of her friends asks if they can bring two friends along as well. How many people are going to Michonne’s birthday party?