The vending machine has been used 30 times, so it has failed to drop a snack 30 / 6 = 5 times. The vending machine has dropped 2 snacks 30 / 10 = 3 times. It has operated normally and dropped 1 snack 30 - 5 - 3 = 22 times. Thus, the vending machine has dropped 22 + 3 * 2 = 22 + 6 = 28 snacks in thirty uses.
The answer: 28
Reverse engineering the question: The vending machine fails to drop a snack when it’s purchased one in six times. One in ten times, it will accidentally drop two snacks. The rest of the time, it drops the purchased snack. If thirty people have used the vending machine once each to purchase a snack, how many snacks has the vending machine dropped?


Reasoning and answer: One dozen of flowers is equal to 1 x 12 = 12 flowers. There are 12 - 2 = 10 flowers that are not daisies. So, 10 x 3 / 5 = 6 of the flowers are tulips. Therefore, there are 10 - 6 = 4 sunflowers.
The answer: 4
What was the question?
Question: Rose bought her mother one dozen flowers. Two of the flowers are daisies. Three-fifths of the remaining flowers are tulips and the rest are sunflowers. How many sunflowers are there?


The cost of the dolls is 3 × $1 = $3. Amy has $100 − $3 = $97 left.
The answer: 97
Reverse engineering the question: Amy's grandfather gave her $100 for her birthday. Amy bought 3 dolls, each of which cost $1. How much money does Amy have left?


Reasoning and answer: Macy used 11 tokens which are worth 15 pitches each, so 11 tokens x 15 pitches = 165 pitches. Piper used 17 tokens x 15 pitches = 255 pitches. Together, Macy and Piper received 165 + 255 = 420 pitches. Macy hit the ball 50 times + Piper’s 55 hits = 105 total hits. Of the 420 pitches – 105 total hits = 315 misses.
The answer: 315
What was the question?
Question: Macy and Piper went to the batting cages. Each token gets you 15 pitches. Macy used 11 tokens and Piper used 17. Macy hit the ball 50 times. Piper hit the ball 55 times. How many pitches did Macy and Piper miss altogether?


Peter is 10 years old because he has 10 birthday candles on his cake. Rupert is 3.5 times older than Peter so Rupert will have 3.5 * 10 = 35 candles on his cake.
The answer: 35
Reverse engineering the question: Peter and his dad Rupert shared the same birthday. To make it special, they each got their own birthday cake. Peter has 10 candles on his cake. Rupert is 3 and 1/2 times older than Peter. How many candles will be on Rupert's cake?


Before washing the car Fred had $14 - $6 = $8. Fred spent half his allowance for the movies, so 2 * $8 = $16 allowance.
The answer: 16
Reverse engineering the question:
Fred spent half of his allowance going to the movies. He washed the family car and earned 6 dollars. What is his weekly allowance if he ended with 14 dollars?