Solution #5: Hands of a Clock

11. It is tempting to give the "obvious" answer 12, but the true answer is 11 as will be found by counting the individual occasions.
  1. Between 6:30 am and 6:35 am.
  2. Between 7:35 am and 7:40 am.
  3. Between 8:40 am and 8:45 am.
  4. Between 9:45 am and 9:50 am.
  5. Between 10:50 am and 10:55 am.
  6. At Noon.
  7. Between 1:05 am and 1:10 am.
  8. Between 2:10 am and 2:15 am.
  9. Between 3:15 am and 3:20 am.
  10. Between 4:20 am and 4:25 am.
  11. Between 5:25 am and 5:30 am.
Source: Longley-Cook, L. H.
Categories: Reasoning, Pitfall
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