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Q: What time is it now, dear R.? (Posted on 2011-09-19) Difficulty: 2 of 5
A: "The time now equals quarter of the time that passed since noon till now plus half of the time left from now till tomorrow's noon."

Please express R's response in HH:MM format.

Abridged from Dudeney's " Amusements in Mathematics" (1917)

See The Solution Submitted by Ady TZIDON    
Rating: 4.6667 (3 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution Good after noon | Comment 2 of 9 |
Let t = hours since noon

Then t/4 + (24-t)/2 = t
        12 = (4/5)t
        t = 48/5 = 9 3/5 = 9:36 pm

Check:
  Hours since noon = 48/5
  Hours till next noon = 24 - t = 72/5
  (1/4)*(48/5) + (1/2)*(72/5) = 12/5 + 36/5 = 48/5

So, 9:36pm is the final answer

  Posted by Steve Herman on 2011-09-19 14:59:58
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