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The archive
Every so often the Archive opens a short case file: a single puzzle, to solve wherever you are.
The alarm clock on the bedside table
released: when the site opened · logic · 4-6 minutes · ages 10+
Archive note. The digital alarm clock on the bedside table shows the hours from 00:00 to 23:59. At 12:21, whoever looked at it noticed that the time reads the same backwards. It isn't the only one.
How many times a day does the clock show a time that reads the same from left to right and from right to left? (a number, in figures or in words)
Try it at home: if you have a digital alarm clock, an oven or a microwave, scroll through the minutes and check the first few.
Spoiler warning: the hint and the solution only open if you press the buttons below.
Look at the minutes. If the hour is 06, the minutes would have to be 60. Do they exist?
16. From 00 to 05, every hour has one: 00:00, 01:10, 02:20, 03:30, 04:40, 05:50. From 10 to 15, another six: 10:01, 11:11, 12:21, 13:31, 14:41, 15:51. From 20 to 23, four: 20:02, 21:12, 22:22, 23:32. The hours from 06 to 09 and from 16 to 19 have none: the minutes would have to start with 6, 7, 8 or 9, and those don't exist. In total 6 + 6 + 4 = 16.
Previous short case files
This is the first short case file: the next ones will be added here, one at a time, and the earlier ones stay available with their solution hidden.
The secret case file
A case file hidden in our channels: scattered fragments that, put together, will form a code. It isn't open yet, and for now there's no code to look for.
When the first fragment is out, we'll say so here, together with the rules. Until then, this door stays shut.