Bucket B has 3 more fruits than C (which has 9 fruits) for a total of 9 + 3 = 12 fruits. Bucket A has 4 more fruits than B (which has 12 fruits) for a total of 12 + 4 = 16 fruits. All three buckets have a total of 9 + 12 + 16 = 37 fruits.
The answer: 37
Reverse engineering the question: Three buckets are holding different fruits. Bucket A has 4 more pieces of fruit than bucket B while bucket B has 3 more pieces of fruit than bucket C. If bucket C has 9 pieces of fruit, how many pieces of fruit are in all 3 buckets?


Reasoning and answer: The total number of apples delivered was: 180 apples x 12 crates = 2160 apples. So, the number of remaining apples after throwing away the rotten ones was: 2160 apples – 160 apples = 2000 apples. And now, we can find the total number of boxes of apples by dividing the remaining number of apples by the number of apples per box: 2000 apples / 20 apples / box = 100 boxes of apples.
The answer: 100
What was the question?
Question: There were 180 apples in each crate. 12 such crates of apples were delivered to a factory. 160 apples were rotten and had to be thrown away. The remaining apples were packed into boxes of 20 apples each. How many boxes of apples were there?


After buying the toy, Isabel has 51 * 2 = 102 dollars left. Isabel had 102 * 2 = 204 dollars at first.
The answer: 204
Reverse engineering the question: Isabel has some money in her piggy bank. She spent half the amount and bought a toy. She then spent half of the remaining money and bought her brother a book. If she has $51 left, how much money, in dollars, did she have at first?


Reasoning and answer: To get the perimeter, you add all the sides o the triangles, so the first two sides add up to 40 + 50 = 90 cm. If the perimeter of the triangle is 160, the remaining side is 160 - 90 = 70 cm.
The answer: 70
What was the question?
Question: The perimeter of a triangle is 160 cm. If two of the sides are 40 cm and 50 cm, calculate the length of the third side?


The two t - shirts amount to $8 x 2 = $16. The two bags amount to $10 x 2 = $20. So Timothy spent $16 + $20 = $36 for the shirts and bags. He still has $50 - $36 = $14 left to spend for the key chains. With the money, he can buy $14 / $2 = 7 sets of key chains. Therefore, he can buy 7 x 3 = 21 pieces of key chains.
The answer: 21
Reverse engineering the question: Timothy has $50 to spend at a souvenir shop. He sees some t-shirts that cost $8 each, key chains that sell 3 pieces for $2, and bags that cost $10 each. Timothy buys 2 t-shirts and 2 bags. How many pieces of key chains can he buy with the amount of money he has left?


Lenny has 20 x 5 = 100 pens. She gave her close friends 100 x 40% = 40 pens. So, 100 - 40 = 60 pens were left. Half of 60 is 60 / 4 = 15 pens. Thus, Lenny has 60 - 15 = 45 pens left.
The answer: 45
Reverse engineering the question:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
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Lenny bought 20 boxes of pens. Each box contained 5 pens. She gave 40% of the pens to her close friends and one-fourth of what's left to her classmates. How many pens were left for Lenny?