Riddles and Brainteasers

On a standard 12 hour clock, the hour and minute hands line up at midnight. Exactly what time (HH:MM:SS) will the hour and minute hands line up again?
 
upstateny said:
On a standard 12 hour clock, the hour and minute hands line up at midnight. Exactly what time (HH:MM:SS) will the hour and minute hands line up again?
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01:05:00? Am I close? Not sure of the exact second. Too lazy to be to accurate.
 
JB1842 said:
01:05:00? Am I close? Not sure of the exact second. Too lazy to be to accurate.
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Close but no cigar. Got to be more accurate. By the time the minute hand gets to the 1 (5-after) the hour hand has moved off the 1.
 
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upstateny said:
Close but no cigar. Got to be more accurate. By the time the minute hand gets to the 1 (5-after) the hour hand has moved off the 1.
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That's ok. I don't smoke. At least I'm not a total dufus and think the answer is 12:00 noon.
 
JB1842 said:
That's ok. I don't smoke. At least I'm not a total dufus and think the answer is 12:00 noon.
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:goofy:That would have been a much worse guess! (And good for you for not smoking.):)
 
upstateny said:
On a standard 12 hour clock, the hour and minute hands line up at midnight. Exactly what time (HH:MM:SS) will the hour and minute hands line up again?
Click to expand...

At 1:00 AM the hour hand is at the 5 minute mark traveling 1/60th as fast as the minute hand, which is at the 0 minute mark. The time t, in minutes after 1 AM, when they meet is, I think:

t = t/60 + 5

solving for t yields:

t = 300/59 = 5.0847457627 minutes

Converting to hours, minutes and seconds:
01:05:05.0847457627

Not sure if I screwed up somewhere....
 
The answer I get is this -

The hands only line up 11 times every 12 hours.

12/11 = 1.0909... hours
.0909... hours * 60 = 5.4545... minutes
.4545... minutes * 60 = 27.2727... seconds

So (to the nearest second) 01:05:27
 
You do realize that 1:05:27 seconds the second hand would be pointing at almost the 6.

The three hands actually never line up exactly except at 00:00:00
 
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EdFred said:
You do realize that 1:05:27 seconds the second hand would be pointing at almost the 6.

The three hands actually never line up exactly except at 00:00:00
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True. That's why the riddle is only for the minute and hour hands.
 
Captain said:
...and the answer is expressed as HH:MM:SS.

That threw me at first too.
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At least I didn't have you try to solve it using a digital clock. :hairraise:

Edit: That reminds me of a riddle that would use a digital clock. Palindromic numbers read the same forward and backward. (Ex: 12321)

What two palindromic times are closest to each other? (Ex: 1:31 and 2:32 are one hour and one minute apart.)
 
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upstateny said:
What two palindromic times are closest to each other? (Ex: 1:31 and 2:32 are one hour and one minute apart.)
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9:59 and 10:01.

Or 8:08 Eastern and 7:07 Central. Never said anything about time zones....

You also didn't say they had to be different times. So, 12:21 and 12:21.
 
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MAKG1 said:
9:59 and 10:01.

Or 8:08 Eastern and 7:07 Central. Never said anything about time zones....
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Ding Ding Ding
We have a winner. Good catch on the time zone, too. I hadn't thought of that.
 
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