perplexus.info :: General : How Long 'til Morning?

How Long 'til Morning? (Posted on 2005-08-09)

I have a clock at home that chimes on every hour and half hour mark. On whole hour marks it chimes once for each hour, and on half hour marks it chimes only once.

One night I was wakened suddenly and realized the the clock had chimed, but I did not know how many times. As I lay awake thinking about nothing in particular I heard the clock chime once and started wondering what time it was.

What is the longest amount of time I would have to lie awake before I knew for sure what time it was?

Submitted by Erik O.

Rating: 2.5000 (8 votes)

Solution: (Hide)

90 minutes
If I was wakened by the clock at midnight, then heard the clock chime at 12:30, I would have to wait 1 hour more to hear the clock chime once two more times before I knew for sure it was 1:30.

If I was wakened by the clock at 12:30 and heard the clock chime once at 1:00, I would have to wait 1 hour more before I knew for sure it was 2:00.

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
Explanation to Puzzle Answer	K Sengupta	2022-05-17 23:54:08
Puzzle Answer	K Sengupta	2022-05-16 23:21:04
the right solution	Vuksa	2006-04-05 11:51:46
re: 1/2 hour	SeaCalMaster	2006-02-09 00:20:26
1/2 hour	Goldwing	2005-09-21 22:45:07
One hour	bo	2005-08-24 18:29:20
re: How Long 'til Morning?	Alex	2005-08-18 21:25:25
not sure if someone said this already, but...	sean	2005-08-15 01:40:06
How Long 'til Morning?	Joe	2005-08-11 20:46:51
Just a little bit longer...	Sam	2005-08-11 19:31:46
My solution	Avinash Narain	2005-08-10 07:31:26
re: Beg to differ with those who beg to differ -with apologies	brianjn	2005-08-10 02:19:17
I thought I'd chime in	Charley	2005-08-10 02:11:15
Beg to differ with those who beg to differ	JoeFish	2005-08-09 19:26:01
re(2): No Subject - To Charlie	pcbouhid	2005-08-09 14:33:05
re: No Subject	Charlie	2005-08-09 13:28:08
No Subject	pcbouhid	2005-08-09 12:02:04
Let me see!!	Kathy	2005-08-09 11:16:09
my solution	lorna	2005-08-09 09:14:46
re: Solution (spoiler) -beg to differ	brianjn	2005-08-09 09:04:48
Little Add-on	JoeFish	2005-08-09 03:06:11
Solution (spoiler)	JoeFish	2005-08-09 03:02:56

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