The task is to generate the correct answer for a given math problem.

Q: Problem: if the radius of a circle is decreased 60 % , what happens to the area ?

A: 84 % decrease
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Q: Problem: a bag contains 12 red marbles . if someone were to remove 2 marbles from the bag , one at a time , and replace the first marble after it was removed , the probability that neither marble would be red is 25 / 36 . how many marbles are in the bag ?

A: 48
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Q: Problem: the current in a river is 10 mph . a boat can travel 50 mph in still water . how far up the river can the boat travel if the round trip is to take 5 hours ?

A:
120
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