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Thursday, February 8, 2007

How many times a day a clock’s hands overlap?

How many times a day a clock’s hands overlap?

2 comments:

  1. In any circular motion, if the ratio between 2 fellow is n:1 then for each lap of the slower fellow, faster fellow overlaps him n times, except for the last lap of the slower fellow, where the number of crossings are n-1. (The race just finishes before the n th cross.
    slower fellow : hour hand (short)
    faster fellow : minuite hand (long)
    n = 12
    Total laps for hour hand = 2
    total overlaps = 12+11 = 23.

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  2. it's 22. Don't listen to the haters

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