Q: a kayaker paddles upstream for 1.5 hours then turns his kayak around and returns to his tent in 1 hour. he travels 3 miles each way. what is the rate of the rivers currents a: 0.5mi/h b: 2mi/h c: 1 mi/h d: 1.5 mi/h

For the first one, it would be a mile every half hour, or a mile and a half every hour. The second one would be 1 mile every twenty minutes. I think it would be safe to say an 1 hour and a half or answer choice "D" for this problem. 

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