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Homework Help: Tricky Algebra well for me

  1. Apr 28, 2015 #1
    1. The problem statement, all variables and given/known data
    A clock gains x min. every 24 hr. If it is y min. slow at present, in how many hours will it show the correct time?

    2. Relevant equations

    3. The attempt at a solution
    I called the current time Tc so
    I have:

    Tc = Tc- y

    I know x will get added to the above equation every 24 hours but I don't know how to connect them. So I get stuck.
    I tried something like (Tc = Tc -y + x)/24 but I don't think this make sense.

    Could someone give me a hint? Help is greatly appreciated.

    (P.S. I know this is simple but do you guys ever buck up on a simple problem that you just can't seem to get out? or do I need to re-study algebra?)
  2. jcsd
  3. Apr 28, 2015 #2
    If it catches up x minutes every 24 hours, how many minutes does it catch up after h hours?
  4. Apr 28, 2015 #3
    It would catch by hx\24 minutes every h hour
  5. Apr 28, 2015 #4
    So how many hours h does it take to catch up y minutes?
  6. Apr 28, 2015 #5
    hx/24y ?
  7. Apr 28, 2015 #6


    This is a rate x time = distance problem

  8. Apr 28, 2015 #7
    Okay that's one part I don't get I didn't have (hx)/24 = y I had (hx)/(24y). I wondering about how to connect x to y , I mean what would make x = y . I'm still a bit confused about the reasoning behind the answer sorry.
  9. Apr 28, 2015 #8
    If a clock gains 2 minutes every hour and it starts out behind by 10 minutes, how long does it take to catch up?

    If a clock gains x/24 minutes every hour and it starts out behind by y minutes, how long does it take to catch up?
  10. Apr 28, 2015 #9
    For the first question it would take 5 hours, but the second one eh I still can't see it. I did the first like so

    if the time was actual time was 12 then the time shown would be 11:50 so after 1 hour(h1) the time would be 12:52 , then 1:54(h2) then 2:56(h3) then 3:58(h4) then 4:00(h5)
    so yeah 5 hours.
  11. Apr 28, 2015 #10
    Ahhhhhhhhhhhhhhh I see it now I am such an idiot. Thank you so much!
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