A 50 cent coin has 12 equal sides. If you place two coins next to each other on a table (see video for diagram), what is the angle formed between the two coins?
This was asked to 12th grade (age 17 and 18) students in Australia. Many were confused and the math problem went viral after they took their frustration to social media.
Can you figure it out? The video presents two methods to solve this problem.
The first solution is an example of a semiregular tessellation (thanks to Mathologer for pointing this out)
Coverage in the media
Thanks to Mathologer for informing me of this puzzle. I referenced his video “Math is Illuminati confirmed” in the video. Check out the video and do subscribe to Mathologer: https://www.youtube.com/watch?v=DfnBW6HvNwM
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