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Error in book? Please confirm.

  1. Jan 19, 2008 #1
    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.

  2. jcsd
  3. Jan 19, 2008 #2
    5:15 + 65 mins. = 6:20...
  4. Jan 19, 2008 #3
    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
  5. Jan 19, 2008 #4
    wow, what a dumb error on my part.

  6. Jan 19, 2008 #5

    haha, thanks.
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