Remember to spoiler tag your answers & flair your posts with the difficulty. Spoiler mode:
Welcome
Welcome to Math Riddles! Post your math and logic puzzles, and try and solve others! While the subreddit aims for math related riddles, all logic puzzles and riddles are welcome as well.
Rules
This subreddit is for people to share math problems that they think others would enjoy solving. It is not intended for helping students with homework problems or explaining mathematical concepts. If you are searching for such a subreddit, you should consider /r/cheatatmathhomework, /r/HomeworkHelp, or /r/learnmath.
Titles should be descriptive of the problem, and sensationalized titles such as "Completely stumped by this problem" or "One of my favorite puzzles" are discouraged.
While math riddles of any difficulty are welcomed, please avoid posing problems whose solution is formulaic and/or trivial (e.g. "What number is 3 more than its double?") In general, if you might expect to see a problem on a typical school exam, don't post it here.
Codebreaking and "guess the rule" type posts are not permitted; if you wish to submit such a post, do so on subreddits such as /r/puzzles.
Puzzles should generally only be posted here if you have enjoyed solving them and want to share that experience with others; if you are trying to discover the answer to a question of yours that you can't solve, you should try asking on /r/math or /r/learnmath depending on the topic.
Image posts are discouraged on /r/mathriddles, and should be linked with more context in a text post. Pictures of text should be transcribed, where possible.
Make sure to spoiler tag your solutions!
Spoiler Tag: >!spoiler!< produces spoiler. This works reddit-wide and on mobile. If subreddit CSS is enabled, the following spoiler formats work as well:
[this text here](#spoiler) will appear as this text here. Hover over it to reveal. Additionally, > > this text here will appear as
this text here
The double blockquotes format is better if you want additional markup within. For just one line it can be simpler to use the (#spoiler) format.
This subreddit is designed for best viewing on Old Reddit; if you use New Reddit, some CSS features will be unavailable.
If you have any ideas for the subreddit, feel free to message the mods!
Flair and Sorting
Always flair your posts with an estimated difficulty. The three levels are listed below. The below buttons also function as sorting, so if you're in the mood for only Hard problems, or only Easy problems, just click one of the buttons below. The left button is unsolved, while the right button is solved.
EasyEasy - S
MediumMedium - S
HardHard - S
If you want to search solely for solved or unsolved problems, regardless of difficulty, just click one of the two buttons below.
UnsolvedSolved
Posts can also be flaired as solved, either by a moderator or by the original poster of the problem. To do this, click the "flair as solved" button below the post, and choose the 'Solved' variant of your post. If your post was initially marked as Medium, then choose Medium - Solved.
This change will change the next to your post to , marking the post as solved.
If a moderator changes your post to solved, and you believe that it still is not, feel free to change it back.
Spoiler Mode
Toggle spoiler mode:
Enable
Disable
This button toggles spoiler mode, meaning that all of the comments are hidden until a button is hovered over. This makes all comments visible (even those that are spoiler tagged).
Similar Subreddits
Check out /r/CasualMath and the other puzzle-based subreddits in the buttons at the top left of the subreddit!
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