## Three Digits in a Row

On a regular 12-hour digital clock how many times would the same three digits in a row be displayed (e.g. 1:11, 11:12, 12:22) in one day?

34 times. These 17 instances will be visible twice in a 24 hour period.

1:11
2:22
3:33
4:44
5:55
10:00
11:10
11:11
11:12
11:13
11:14
11:15
11:16
11:17
11:18
11:19
12:22

Posted in Brain Teasers

4 Comments on "Three Digits in a Row"

July 27, 2018 @ 20:24

What about when the date changes and it turns to 00:00, and then there will be 00:01, 00:02, 00:03, 00:04, 00:05, 00:06, 00:07, 00,08, 00:09? Do they not count??

You only see 00:00 on a 24-hour clock. The riddle explicitly states, “a regular 12-hour digital clock”.

jayjay says
August 21, 2021 @ 17:54

its 66 times

12:11 AM 12:11 PM
12:22 AM 12:22 PM
01:00 AM 01:00 PM
01:11 AM 01:11 PM
02:00 AM 02:00 PM
02:22 AM 02:22 PM
03:00 AM 03:00 PM
03:33 AM 03:33 PM
04:00 AM 04:00 PM
04:44 AM 04:44 PM
05:00 AM 05:00 PM
05:55 AM 05:55 PM
06:00 AM 06:00 PM
07:00 AM 07:00 PM
08:00 AM 08:00 PM
09:00 AM 09:00 PM
10:00 AM 10:00 PM
10:11 AM 10:11 PM
11:00 AM 11:00 PM
11:01 AM 11:01 PM
11:10 AM 11:10 PM
11:12 AM 11:12 PM
11:13 AM 11:13 PM
11:14 AM 11:14 PM
11:15 AM 11:15 PM
11:16 AM 11:16 PM
11:17 AM 11:17 PM
11:18 AM 11:18 PM
11:19 AM 11:19 PM
11:21 AM 11:21 PM
11:31 AM 11:31 PM
11:41 AM 11:41 PM
11:51 AM 11:51 PM

Matt says
July 21, 2022 @ 12:46

The previous answer misses one of the criteria of the riddle. The riddle doesn’t ask how many times will the same 3 digits be displayed. It asks how many times will the clock display the same three digits in a row.

To make this more easily viewable, I’m going to start at 1AM.

In a twelve hour period, the same 3 digits in a row will be displayed 17 times.

Since it’s a 12-hour clock, that number has to be doubled to account for AM/PM to get the answer to the riddle.

Therefore, the answer is 34.

1:11 AM/PM
2:22 AM/PM
3:33 AM/PM
4:44 AM/PM
5:55 AM/PM
10:00 AM/PM
11:10 AM/PM
11:11 AM/PM
11:12 AM/PM
11:13 AM/PM
11:14 AM/PM
11:15 AM/PM
11:16 AM/PM
11:17 AM/PM
11:18 AM/PM
11:19 AM/PM
12:22 AM/PM