The school bought 2 x 2 = 4 dinosaur models for the elementary library. So the school bought a total of 2 + 4 = 6 models. The price of each model was reduced by $100 x 5 / 100 = $5. Thus, each model cost $100 - $5 = $95. Therefore, the school paid a total of $95 x 6 = $570.
The answer: 570
Reverse engineering the question: The Science museum sells dinosaur models for $100 each. A certain school bought 2 models for the kindergarten library and also bought twice as many for the elementary library. Since the school bought more than 5 models, there was a 5% reduction in price for each model. How much did the school pay in all?


Reasoning and answer: At $3 a dozen, Krista sold $120 / $3 = 40 dozen eggs. If 10 hens laid 40 dozen eggs in 4 weeks, that means 40 dozen eggs / 10 hens = 4 dozen eggs were laid by each hen in four weeks. To find out how many eggs each hen laid in a week, 4 dozen eggs / 4 weeks = 1 dozen eggs each week. Since a dozen has 12 eggs, each hen lays 12 * 1 = 12 eggs each week.
The answer: 12
What was the question?
Question: Krista started raising chickens. She has 10 hens who lay eggs. She sells the eggs for $3 a dozen. In four weeks, she sold $120 worth of eggs. If she sold all the eggs her hens laid, how many eggs does each hen lay a week?


Let x be the number of birds on the fence. We know that 10 + 2 * x = 50. Subtracting 10 from both sides, we get 2 * x = 50 - 10 = 40. Dividing both sides by 2, we get x = 20.
The answer: 20
Reverse engineering the question: Ten more than twice the number of birds on the fence is 50. How many birds are on the fence?


Reasoning and answer: Cassy can pack 12 x 10 = 120 jars of jam in the 10 boxes. She can also pack 10 x 30 = 300 jars of jam in the 30 boxes. A total of 300 + 120 = 420 jars of jam can be packed in the boxes. So, 500 - 420 = 80 jars of jam will be left unpacked.
The answer: 80
What was the question?
Question: Cassy packs 12 jars of jam in 10 boxes while she packs 10 jars of jam in 30 boxes. If she has 500 jars of jams, how many jars of jam will she have left when all the boxes are full?


He gave 23 cards each to 15 students for a total of 23 * 15 = 345 cards. He has 12 cards left, so originally the number of cards was 345 + 12 = 357 cards.
The answer: 357
Reverse engineering the question: Joseph gave 23 cards to each of his 15 students and had 12 cards left. How many cards did Joseph have at first?


The cost will for 3 adults will be $12 / adult x 3 adults = $36. The cost for 3 children will be $10 / child x 3 children = $30. The total cost will be $36 + $30 = $66.
The answer: 66
Reverse engineering the question:
Julia is performing in her high school musical this weekend and her family wants to come to the show. Tickets are $12 for adults and $10 for children. If her mom, dad, grandma, and three little sisters come to the show, how much will the total be for their tickets?