xkcd #3138: Dimensional Lumber Tape Measure
Title text:
A person with two watches is never sure what time it is, especially if I got them one of the watches.
Transcript:
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Source: https://xkcd.com/3138/
If it's used for surveying, aren't those survey feet? (a survey foot is 1.000002 US customary feet). Dividing a survey foot by 12 would not be technically an inch, even though it's only a couple millionths off.