Error in book? Please confirm.

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The discussion revolves around a math problem involving a train and a car traveling parallel to each other. The train crosses a river at 5:00 PM, followed by the car 15 minutes later. Calculations show that the car will pass the train 65 minutes after it starts, resulting in a time of 6:05 PM. However, the answer of 6:05 PM is not listed among the provided choices, leading to confusion. The conversation concludes with a light-hearted acknowledgment of a mistake in the initial calculations.
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A highway and a train track run parallel to each other. At 5:00 a train crosses a river. Fifteen minutes later, a car, traveling in the same dirrection, crosses the river. The train's average speed is 52mph, the car's is 64mph. When will the car pass the train?

15 minutes = 1/4hour, so train traveling 52mph is 13 miles away from the car over the river.

64 - 52 = The vehicles are converging at a rate of 12mph.

From D = RT, T = D/R. So,

T = 13/12

13/12 = 1 and 1/12th of an hour, or 65 minutes.

The car should pass the train in 01:05, or at 6:05.

This answer is not listed among the choices.

WTF?
 
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5:15 + 65 mins. = 6:20...
 
and also, i can't help myself, maybe you would've gotten 6:20 with a graphing calculator :)

jk. although i do love my ti83
 
matticus said:
5:15 + 65 mins. = 6:20...

wow, what a dumb error on my part.

Thanks.
 
matticus said:
and also, i can't help myself, maybe you would've gotten 6:20 with a graphing calculator :)

jk. although i do love my ti83


haha, thanks.
 
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