You can paddle your canoe seven miles per hour through any placid lake. The stream flows at three miles per hour. The moment you start to paddle up stream a fisherman looses one of his bobbers in the water fourteen miles up stream of you.
How many hours does it take for you and the bobber to meet?
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Monday, November 08, 2010
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My 11 year old daughter and I think it will take 2 hours for the bobber and canoe to meet.
ReplyDeleteI think that it would be determined by which way the stream is moving, maybe?
ReplyDelete2 hrs.
ReplyDelete4 hours. The 7 mph becomes 4 mph once you subtract the stream current.
ReplyDeleteViolet and Ms McNeilly/Mrs Salazar and her 11 year old daughter have it right, it will take 2 hours.
ReplyDeleteI believe traveling upstream means you are traveling against the current anonymous.
It takes two hours, as the bobber travels at 3 mph, it will be six miles closer to you in two hours. Assuming you don't tire out, in two hours you will have traveled (7-3)*2 = 8 miles. That puts you next to the bobber.