First find the total number of sheep by dividing the number rounded up by 90%: 81 sheep / .9 = 90 sheep. Then multiply that number by 10% to find the number that are in the hills: 90 sheep * 10% = 9 sheep.
The answer: 9
Reverse engineering the question: Carla's sheepdog rounded up 90% of her sheep, but the remaining 10% wandered off into the hills. If there are 81 sheep in the pen, how many are out in the wilderness?


Reasoning and answer: First add the number of snowballs each person made to find the total: 50 snowballs + 150 snowballs = 200 snowballs. Then divide the number Janet made by the total number and multiply by 100% to express the answer as a percentage: 50 snowballs / 200 snowballs * 100% = 25%.
The answer: 25
What was the question?
Question: Janet makes 50 snowballs and her brother makes 150 snowballs. What percentage of the snowballs did Janet make?


James is 35 - 23 = 12 years younger than John. 5 years less than Tim's age is 79 - 5 = 74 years old. So John is 74 / 2 = 37 years old. That means James is 37 - 12 = 25 years old.
The answer: 25
Reverse engineering the question: James turned 23 the same time John turned 35. Tim is 5 years less than twice John's age. If Tim is 79 how old is James?


Reasoning and answer: Frank bakes 2 * 12 = 24 cookies per day. Frank bakes a total of 24 * 6 = 144 cookies. Frank eats 1 * 6 = 6 cookies. After Ted leaves, there are 144 - 6 - 4 = 134.
The answer: 134
What was the question?
Question: Frank bakes two trays of cookies per day, for 6 days. Frank eats one cookie each day to make sure they taste good. Ted comes over on the sixth day and eats 4 cookies. If each tray makes 12 cookies, how many cookies are left when Ted leaves?


Arnel shared 5 x 8 = 40 pencils with his friends. So, he had 10 + 40 = 50 pencils in all. Therefore, each box had 50 / 10 = 5 pencils inside.
The answer: 5
Reverse engineering the question: Arnel had ten boxes of pencils with the same number of pencils in each box. He kept ten pencils and shared the remaining pencils equally with his five friends. If his friends got eight pencils each, how many pencils are in each box?


The cost Rachel should budget for her pair of shoes is $50 * 2 = $100. The cost Rachel should budget for her dress is $200 * 2 = $400. The total Rachel should budget is $100 + $400 = $500.
The answer: 500
Reverse engineering the question:
Rachel and Sara want to attend a beauty and modeling contest. They both want to buy new pairs of shoes and dresses. Sara buys a pair of shoes which costs $50 and a dress which costs $200. How much should Rachel budget if she wants to spend twice as much as what Sara spent on the pair of shoes and dress?