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Word Question Help

  1. Sep 12, 2008 #1
    Jake's kitchen clock had stopped at 2:00 pm and he replaced the battery not knowing the exact time. He then rode to visit Avon, arriving at 3:15 pm and leaving at 4:45 pm. If when he arrived home the kitchen clock said 5:30 pm, what was the correct time?

    This was a question a friend gave me and I couldn't get my head around it to solve it. I think I am having the problems solving it because I don't really know if the specified times of 3:15 pm and 4:45 pm are off of his re-set clock or another clock variable. Also not knowing the amount of time it took him to ride to Avon's and home confused me.

    I am not particularly good at maths, but I would greatly appreciate a way to solving this question in simple terms so I can grasp the concept:smile:
  2. jcsd
  3. Sep 12, 2008 #2


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    The old clock says the trip (both ways, including the time Jake stayed) took 5:30 - 2:00 = three and a half hours. The actual time when he arrived at Avon was 3:15; the actual time when he left for home was 4:45.
  4. Sep 12, 2008 #3
    I am still having trouble interpreting this.. So he spent 3 and half hours at Avon's & getting there both ways. We spent the duration of 1h 30 minutes at Avon's, therefore the rest was spent riding - 2 hours. You would assume he would take the same way to get back, so, each way was 2 hours divided by 2 = 1 hour to get back home: 4:45 + 1h = 5:45pm when he got home? If that is the case, the clock is therefore 15 minutes slow or out of tune.
    Last edited: Sep 12, 2008
  5. Sep 12, 2008 #4


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    Perhaps you're just not clear on exactly what assumptions you should be making in order to solve this. Try the following.

    1. Assume that jake set out for Avon's immediately after replacing the battery.

    2. Assume that the times of 3:15pm and 4:45pm are measured by Avon's clock which is accurate.

    3. Assume that each way of Jakes trip to/from Avons takes the same time.
  6. Sep 12, 2008 #5

    Okay, I think I got the answer right in my second post:

    If the re-set clock read 2:00 pm and when he arrived home it read 5:30 pm that means 3 and half hours was the duration of Jake's entire trip. We have the accurate time from Avon's clock - 3:15 pm and leaving at 4:45 pm. The time spent at Avon's was 1 and a half hours. This leaves 2 hours for riding there and back, and if we assume both trips took the same amount of time that would equate to 1 hour. The time Jake left Avon's was 4:45 pm and if it took an hour to get home, therefore the time would be 5:45 pm.

    Please tell me if I am right, or just completely wrong :blushing:
  7. Sep 13, 2008 #6


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    Yes mech you were correct in your second post, his clock is 15 min slow.

    BTW. The only reason that I posted those hints was because I hadn't refreshed the page for about an hour we I replied yesterday, so I hadn't seen your reply before I posted.
  8. Sep 14, 2008 #7
    Thank you for your help nonetheless!

    And I can relate to that, I do it frequently on other forums - leave and forget to refresh.
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