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:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3138/
The joke is when you purchase a 2x4, it measures 1.5x3.5 and not the advertised 2x4.
lol, learn something new every day!