.
. .
 
 
Subj:.....Chiming Clock (S642)
          From: Puzzles And Brain Teasers
          on 4/27/2008
Drawing from OO.com.au...

Source:
http://www.afunzone.com/adailypuzzle/04-27-09.html

.

A grandfather clock chimes the appropriate number of 
times to indicate the hour, as well as chiming once at 
each quarter hour.  If you were in another room and 
heard the clock chime just once, what would be the 
longest period of time you would have to wait in order 
to be certain of the correct time? 

.
.
Finger pointing down
from darrell94590 on 1/2/2006
.
 
 
 
Drawing from Ripleys-Believe It Or Not
.

              THE SOLUTION
 

You would have to wait 90 minutes between 12:15 and 1:45.
Once you had heard seven single chimes, you would know
that the next chime would be two chimes for 2 o clock.

.
.