247: Factoring the Time

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Factoring the Time
I occasionally do this with mile markers on the highway.
Title text: I occasionally do this with mile markers on the highway.


The man at the desk is bored and so decides to prime factorize the time as shown on the clock. Annoyed, the man on the computer decides to switch the clock from 12-hour time (2:53 pm) to 24-hour time (14:53). This proves to be a much tougher job to factorize before the time changes, as the time now shown is a four digit number rather than a three digit number. The man at the desk has been at it for almost 2 hours (1:00 - 2:53). This is also a play on the phrase "Factoring the time", meaning taking the time required to do something or the current time into account when making a decision. There is a widget for OS X to display the current time and its prime factors.

It's likely the man at the computer switched the clock because he's been hard at work this whole time, and he's irritated that the man at the desk has been doing this pointless task for the last hour and 53 minutes.

The title text refers to doing something similar with mile marker signs, hopefully not while driving as this could be considered distracted driving.

Also, 1,453 is a prime number.


[One man is sitting at a computer. Another man is sitting at a separate desk. There is a clock which reads 2:53]
Man at desk: 253 is 11x23
Man at computer: What?
Man at desk: I'm factoring the time.
Man at desk: I have nothing to do, so I'm trying to calculate the prime factors of the time each minute before it changes.
Man at desk: It was easy when I started at 1:00, but with each hour the number gets bigger
Man at desk: I wonder how long I can keep up.
[Man at desk reaches back and touches the clock] <<BEEP>> [Clock now reads 14:53]
Man at desk: Hey!
Man at computer: Think fast.



I used to find the prime factors of the remaining distance until the next turn. It starts off difficult (for me) at 99 miles, etc. When it gets down to 30 miles, it gets easier. Then, at 9.9 miles, I have a tenth the time to factor 99 again, and it gets easier as the numbers get smaller. This is actually a pretty good way to pass the time while driving. (talk) (please sign your comments with ~~~~)

Paying attention to your driving might be a benefit. To yourself and others. Just sayin'.Jakee308 (talk) 20:00, 24 April 2015 (UTC)

I wonder how much time Randall spent trying to find a time that is not prime but the time + 1200 would be. -- Flewk (talk) (please sign your comments with ~~~~)

Took me about 5 minutes with a script after getting a list of primes from the internet: 1:19; 1:21; 2:09; 2:47; 2:53; 2:59; 3:23; 3:43; 4:07; 4:13; 4:27; 4:37; 5:33; 5:53; 5:59; 6:11; 6:23; 7:07; 7:13; 7:31; 7:49; 8:03; 8:17; 9:13; 9:31; 9:43; 10:03; 10:07; 10:37; 10:43; 11:11; 11:33; 11:39; 11:41; 11:47; 11:57 (also the technical cases of: 12:03; 12:05; 12:07; 12:11; 12:19; 12:41; 12:43; 12:47; 12:53) . -- 06:18, 20 January 2016 (UTC)

You know, in the state of Massachusetts, which is where Randall said he lives in the book What If?, mile markers on the highway are placed every 0.2 miles, so he would get only twelve seconds per marker if he's trying to do each and every one (less if he's slightly speeding like everyone else does when there's no traffic). 02:09, 22 February 2016 (UTC)

I added another explanation for the title text. It seems to me that factoring the (often same) mile marker numbers is a bit boring. Lanmi (talk) 11:55, 23 April 2016 (UTC) Lanmi

Why would factoring become secondary problem after switching to km?

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