The task is to generate the correct answer for a given math problem.
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Question: Problem: find the sum the difference between the compound and s . i . on a certain sum of money for 5 years at 20 % per annum is rs . 75 of money ?

Answer: 1875


Question: Problem: if 1 / ( x + 4 ) + 1 / ( x - 4 ) = 1 / ( x - 4 ) , what is the value of x ?

Answer: 4


Question: Problem: one copy machine can make 20 copies a minute , and a second copy machine makes 10 copies a minute . if the two copiers work together , how long would it take them to make 900 copies ?

Answer:
30 minutes