The task is to generate the correct answer for a given math problem.
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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: | x + 3 | – | 4 - x | = | 9 + x | how many solutions will this equation have ?

Answer: 1


Question: Problem: yesterday it took robert 3 hours to drive from city a to city b . today it took robert 2.5 hours to drive back from city в to city a along the same route . if he had saved 30 minutes in both trips , the speed for the round trip would be 80 miles per hour . what is the distance between city a and city b ?

Answer:
180