1. Standard memberwolfgang59
    howling mad
    In the den
    Joined
    09 Jun '07
    Moves
    45641
    30 Dec '13 01:431 edit
    EASY one for your kids!

    The two hands on a clock are exactly at right-angles, when will that next occur?
  2. Joined
    07 Jul '12
    Moves
    1783
    30 Dec '13 10:32
    32 minutes and 44 seconds later.
  3. Standard memberwolfgang59
    howling mad
    In the den
    Joined
    09 Jun '07
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    45641
    30 Dec '13 21:19
    Originally posted by Sebastian Yap
    32 minutes and 44 seconds later.
    Close enough! 😀
  4. Subscribertalzamir
    Art, not a Toil
    60.13N / 25.01E
    Joined
    19 Sep '11
    Moves
    45045
    18 Jan '14 23:24
    Every hour, the minute hand goes 360 degrees and the hour hand 30 degrees, so X hours = minute hand gains 330 times X degrees. To gain exactly 180 degrees that's 180 / 330 hrs, or 60 x 180 / 330 minutes. That is, 32 minutes and 43 7/11 seconds.. doesn't even depends on whether you start at the hands at the 3 o'clock or the 9 o'clock position.
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