The task is to generate the correct answer for a given math problem.
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Question: Problem: how many prime numbers are between 51 / 13 and 89 / 9 ?

Answer: 2


Question: Problem: mixture contains alcohol and water in the ratio 4 : 3 . if 5 liters of water is added to the mixture , the ratio becomes 4 : 5 . find the quantity of alcohol in the given mixture .

Answer: 10


Question: Problem: the age of somu is one - third his father ' s . 7 years back he was one - fifth of his father ' s age . what is his persent age ?

Answer:
14