247: Factoring the Time

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(253 isn't a prime number.)
(Explanation: 1 is not a prime number)
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==Explanation==
 
==Explanation==
[[Cueball]] is bored and so he does prime factorize the time shown at the clock. He's been doing this for almost two hours (from 1:00 pm to 2:53 pm). The number 1 is the smallest prime but 253 is in fact not a prime because it can be divided by 11. His co-worker is likely annoyed at this inactivity, and so he switches the clock from 12-hour time (2:53 pm) to 24-hour time (14:53). This makes factorization more difficult, as the time now shown is a four digit number rather than a three digit number. The number 1,453 is a prime number as well, but Cueball has only one minute to solve this.
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[[Cueball]] is bored and so he does prime factorize the time shown at the clock. He's been doing this for almost two hours (from 1:00 pm to 2:53 pm). The number 2 is the smallest prime but 253 is in fact not a prime because it can be divided by 11. His co-worker is likely annoyed at this inactivity, and so he switches the clock from 12-hour time (2:53 pm) to 24-hour time (14:53). This makes factorization more difficult, as the time now shown is a four digit number rather than a three digit number. The number 1,453 is a prime number as well, but Cueball has only one minute to solve this.
  
 
This comic is also a play on the phrase "factoring the time", which means taking time to make sure one has sufficient time.
 
This comic is also a play on the phrase "factoring the time", which means taking time to make sure one has sufficient time.

Revision as of 10:22, 18 October 2013

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.

Explanation

Cueball is bored and so he does prime factorize the time shown at the clock. He's been doing this for almost two hours (from 1:00 pm to 2:53 pm). The number 2 is the smallest prime but 253 is in fact not a prime because it can be divided by 11. His co-worker is likely annoyed at this inactivity, and so he switches the clock from 12-hour time (2:53 pm) to 24-hour time (14:53). This makes factorization more difficult, as the time now shown is a four digit number rather than a three digit number. The number 1,453 is a prime number as well, but Cueball has only one minute to solve this.

This comic is also a play on the phrase "factoring the time", which means taking time to make sure one has sufficient time.

The title text refers to a similar challenge involving mile markers. At highway speeds (60+ mph), they would show up at least once per minute. Combined with the distraction of driving, factorizing numbers in time becomes much more difficult.

Transcript

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

Trivia

  • There is a widget for OS X to display the current time and its prime factors.
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Discussion

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. 108.162.219.202 (talk) (please sign your comments with ~~~~)
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