Please help contribute to the Reddit categorization project here

    HarryPotter5777

    + friends - friends
    26,607 link karma
    23,626 comment karma
    send message redditor for

    [–] Mathriddle me this please Reddit! HarryPotter5777 1 points ago in mathriddles

    Hi there!

    This is a subreddit for deterministic puzzles whose solution is entirely mathematical in nature; despite the name, cryptic riddles which are merely about numbers aren't what we aim for here, so your post's been removed. Try cross-posting to subreddits like /r/riddles and /r/puzzles instead.

    [–] King and wise jeweller's Gold ring Mathematical puzzle HarryPotter5777 2 points ago in mathriddles

    You're linking to your own site a lot, which can be OK in some cases if the puzzles really are better appreciated on an external site, but in many cases the puzzles you link would work better as a text post. They're also reposts much of the time, which those of us who've been here a while find a bit annoying since we've seen them before (though as a new user it's not reasonable to expect you to know which ones have already shown up over the years).

    [–] King and wise jeweller's Gold ring Mathematical puzzle HarryPotter5777 2 points ago in mathriddles

    Agreed, but certainly not an automated one, and their posts are often in fact suitable for the sub; this hasn't been much of an issue in the past, but if there are a lot more, we might add a rule against excessive self-promotion.

    [–] Solve this unbeatable finance question! very hard. HarryPotter5777 1 points ago in mathriddles

    From the sidebar:

    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.

    As such, your post has been removed. If you violate the rules again, you may be banned.

    [–] Choose 4 points at random on the surface of a sphere. What is the probability that the tetrahedron they form contains the center? HarryPotter5777 1 points ago in mathriddles

    This is true, but say your sphere was the Earth, and your three points were NYC, Mexico City, and Rio de Janeiro. If your hemispheres had been the north and south hemispheres, you'd think they weren't all on the same hemisphere, but if you split things east and west, they would be.

    [–] How would you solve for n? HarryPotter5777 1 points ago in mathriddles

    From the sidebar:

    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.

    As such, your post has been removed.

    [–] King and wise jeweller's Gold ring Mathematical puzzle HarryPotter5777 1 points ago in mathriddles

    Please flair your post! Flair options should be available beneath the body of your post in red text.

    [–] Choose 4 points at random on the surface of a sphere. What is the probability that the tetrahedron they form contains the center? HarryPotter5777 7 points ago in mathriddles

    I think the one you're thinking of is the Bertrand paradox about randomly chosen chords on a circle, where there are some legitimately different reasonable ways to choose a "random" distribution. But there's really only one nice way to pick points on a sphere - the uniform distribution where the probability that a point lies in some region is exactly proportional to the surface area of that region. I considered adding "uniform" to the problem description, but figured it was clear from context - is there another distribution over the surface of a sphere you know of?

    [–] Find 10 digit secret number HarryPotter5777 1 points ago in mathriddles

    Please flair your post! Flair options should be available beneath the body of your post in red text.

    [–] A riddle a made for some friends a while ago which I now no longer know how to solve HarryPotter5777 1 points ago in mathriddles

    From the sidebar:

    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.

    As such, your post has been removed.

    [–] Watermelon HarryPotter5777 1 points ago in mathriddles

    It is; that's why it became the third-highest post of all time on this sub when posed as a puzzle in its own right (link). The point isn't the objective quality of the riddle, but the incentives it leads to; if /r/mathriddles becomes "that place with a bunch of people who will answer your homework questions for you", the sub drops precipitously in quality from everyone spamming it, even if a few of those homework questions are interesting in their own right now and then.

    [–] Number3629: Needs More Skulls HarryPotter5777 12 points ago in questionablecontent

    Same here! I'm glad everyone else is warming up to the arc over time.

    also *they

    [–] Monty Hall Problem question HarryPotter5777 1 points ago in mathriddles

    From the sidebar:

    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.

    As such, your post has been removed. If you're looking for an explanation on this topic, consider posting to one of the above subreddits or /r/math; alternatively, Google the problem a bit - there are a quite a few in-depth explanations of why this reasoning is fallacious, as well as a few preexisting threads on /r/math, I believe.

    Very briefly: the third door being removed gave you no useful information since you knew a door other than your own was going to be removed anyway. You can find more detailed explanations by using some of the above resources.

    [–] Watermelon HarryPotter5777 1 points ago in mathriddles

    From the sidebar:

    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.

    As such, your post has been removed.

    [–] Watermelon HarryPotter5777 1 points ago in mathriddles

    Please don't solve other people's homework problems here; it encourages them to post more on this sub, instead of going to the appropriate locations to get feedback.

    [–] 3628: Status Report HarryPotter5777 23 points ago in questionablecontent

    One that gets (possibly) hacked by the Red Chinese though!

    [–] 3628: Status Report HarryPotter5777 15 points ago in questionablecontent

    Fair enough, though Jeph's pulled the "response on the phone to something ridiculous on the other line" gag before with someone who'd plausibly do it.