Yesterday, his shop washed 5 + 5 = 10 kilos of laundry. Today, it washed 2 x 10 = 20 kilos of laundry. Thus, Oliver's shop washed a total of 5 + 10 + 20 = 35 kilos of laundries for three days. Therefore, his shop earned 35 x $2 = $70 for three days.
The answer: 70
Reverse engineering the question: Oliver owns a laundry shop, and he charges $2 per kilo of laundry. Two days ago, his shop washed a total of 5 kilos of laundries. Yesterday, it washed five kilos of laundries more than the previous day. Today, it washed twice the number of kilos than yesterday.  How much did he earn for three days?


Reasoning and answer: After five days, Chantel has 5 * 2 = 10 bracelets. Then she has 10 - 3 = 7 bracelets. After the next four days, she makes 4 * 3 = 12 bracelets. In the end, Chantel has 7 + 12 - 6 = 13 bracelets.
The answer: 13
What was the question?
Question: For 5 days, Chantel makes 2 friendship bracelets every day. She gives away 3 bracelets to her friends at school. Then for four days, she makes 3 friendship bracelets every day. Then she gives away 6 bracelets to her friends at soccer practice. How many bracelets does Chantel have in the end?


Matt used 4 * 5 = 20 pounds of flour. That means he made 20 / 2 = 10 batches. So he cooked 10 * 12 = 120 cookies. After Jim eats 15 there are 120 - 15 = 105 cookies left.
The answer: 105
Reverse engineering the question: Matt can make a batch of a dozen cookies using 2 pounds of flour. He uses 4 bags of flour each weighing 5 pounds. If Jim eats 15 cookies how many cookies are left?


Reasoning and answer: 75% of the 8 holes in Maynard's lawn, or (75 / 100) * 8 = 6 holes, were filled in with dirt. Of the original 8 holes, 8 - 6 = 2 holes remain unfilled.
The answer: 2
What was the question?
Question: Maynard's dog dug 8 holes in the lawn. Maynard filled in 75% of the hole with dirt. How many holes remain unfilled?


After getting six games from Henry, Neil has 6 + 7 = 13 games. Now, Henry has 13 * 4 = 52 games. Henry had 52 + 6 = 58 games at first.
The answer: 58
Reverse engineering the question: Henry had some games, and he gave six of them to Neil. Now, Henry has 4 times more games than Neil. If Neil had 7 games at first, how many games did Henry have at first?


On the bus, the number of Dutch people was 3 / 5 of the total number, a total of 3 / 5 * 90 = 54 people. Out of the 54 people who were Dutch, 1 / 2 were Dutch Americans, a total of 1 / 2 * 54 = 27 people. If 1 / 3 of the passengers on the bus identifying as Dutch Americans sat at the windows, their number is 1 / 3 * 27 = 9.
The answer: 9
Reverse engineering the question:
Of the 90 people on William's bus, 3/5 were Dutch. Of the 1/2 of the Dutch who were also American, 1/3 got window seats. What's the number of Dutch Americans who sat at the windows?