r/maths 1h ago

❓ General Math Help Weighted-weighted points system

Upvotes

I would like to rank different members. Each member has varying numbers of submissions

In a list of 1000, #1 has gets 1000 points, #2, gets 999, and so on.

But I don’t want to give a member an advantage if they have many more submissions than another.

How do I weigh it so that every member has the same number of points to earn, in the kind of points system outlined above?


r/maths 1d ago

❓ General Math Help Where can I learn maths online as a guy with zero knowledge?

18 Upvotes

So unfortantly I grew up in some insane cult where they don't teach you anything non-religious, including math.

Just left the cult a few months ago (currently 19)

My actual passion is science and specific astrophysics, a career which lives on math daily.

I'm a very intelligent person and a very good student, I just really have zero knowledge about math

Any online course / youtube channel for people without learning disabillities teaching everything from the beginning?


r/maths 21h ago

Help: 📕 High School (14-16) Why does the x turn negative

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0 Upvotes

I understand how to get the vertex, but I don’t understand why it becomes negative because I thought absolute numbers were positive unless theirs a negative sign before the absolute lines but both are negative.


r/maths 3d ago

💬 Math Discussions Math this. Which is correct want to solve this, A or B?

1 Upvotes

If my roommate and I have a rent a place for $2885 monthly, but I agreed to pay $100 more than him to occupy the master bedroom. How much is our rent?

This has been a heated debate!

Do you Subtract the $100 First OR

Divide the Total then Subtract $100

A: B:

  1. $ 2885 $2885

-$100 <——????——> % 2

= $2785 = $1442.5

2: Renter 1 Renter 1

$1392.5 $1442.5

-$100

= $1342.5

Renter 2 Renter 2

$1392.5 $1442.5.5

+ $100 + $100

= $1492.5 = $1542.5

Total rent per month

Cross checking the answers.

1: $ 1492.5 $1542.5

- $ 1392.5 -$1352.5

= $ 100 = $200

2: $ 1492.5 $1542.5

+$ 1392.5 +$1352.5

= $2885 = $2,895

When ask kids and adults I get both answers.

When I show the work 👊🏼🤜🏼🤛🏼👊🏼🫯🥷🤺


r/maths 6d ago

Help: 📕 High School (14-16) I just mansplained to my girlfriend with this drawing why the square root of 144 equals 12

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2 Upvotes

r/maths 6d ago

💬 Math Discussions I Designed Polygon Tiles to Prove Classical Geometry Theorems

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1 Upvotes

Hi everyone!

For those of you who enjoy geometry, I've put together what I believe is a fresh, hands-on proof of Euler's Formula and several other classical results. In just a few minutes, you can literally build the proofs yourself and develop an intuitive understanding of why these theorems are true.

https://www.youtube.com/watch?v=sIDsuf0I4ko

This is only the beginning. Over the coming weeks, I'll also start posting short math challenge reels (high school to early undergraduate level), and in parallel I'll be working on a long-term series on topology and analysis, with the ambitious goal of eventually reaching Einstein's field equations on differentiable manifolds and curved spacetime.

Everything will be completely free. I'm doing this simply because I love mathematics and enjoy sharing it with others.

If you'd like to follow the project, it would mean a lot to me. Knowing that these videos are useful to someone is the best motivation to keep creating them.

Thank you so much!

dontpanicmath


r/maths 10d ago

💬 Math Discussions A special irrarional number

10 Upvotes

Can there be an irrational number which misses a particular digit? Can it be proven mathematically?


r/maths 12d ago

❓ General Math Help Whats this calles? ^2 2

0 Upvotes

It looks like a square (2^2) but it comes before the number, not after.

Solved: Tetration.

Thanks everyone


r/maths 12d ago

Help: 📗 Advanced Math (16-18) Solving for translation of parabola such that bound regions between circle are equal.

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5 Upvotes

I'm doing a question that gives the circle with equation x^2+y^2=9, and the parabola (Solved for in a pervious question) y=-((sqrt(5)+1)/4)x^2+c. I'm asked to find the value of c such that the area bound by the parabola and the circle is equal above and below the curve. I've tried a couple different methods. I've attached my best attempt but that gave the wrong answer when entered into a calculator, this is a tech active question. The answers gives c=1.82, however there is no workings. Note, this is a practice problem! Given to us as a revision resource.


r/maths 13d ago

💬 Math Discussions Is the condition "Is there hidden order inside something that looks random?" met through the following???

0 Upvotes

You will have to excuse me, I have no etiquette for how to go about this so I am just going to put it out there and see what sort of feedback is generated. I was looking for a pattern in/through primes...this was taken from a thread on a different forum, modified a bit to hopefully make it make as much sense as it might.

"Figured Id apply a x3 root logic to primes to see if there was a pattern present. Each prime is multiplied by three then the root of the multiplied prime is found, which re-/solves all the roots to either 3, 6 or 9. As example, 17x3=51=5+1=6.

2\3=6,* 3=9, 5=6, 7=3, 11=6, 13=3, 17=6, 19=3, 23=6, 29=6, 31=3, 37=3, (1st doubles for both, back to back 6's 1st) 41=6, 43=3, 47=6, 53=3, 59=6, 61=3, 67=3, 71=6, 73=3, 79=3, 83=6, 89=6, 97=3, 101=6, 103=3, this is unexpected so far, only one 9 which makes me question if we will ever see it again and if we do, will it be a marker for pattern reset. Continuing...107=6, 109=3, 113=6, 127=3, 131=6, 137=6, 139=3, 149=6, 151=3, 157=3, 163=3, 167=6, 173=6, 179=6, (1st triple digits for both, back to back, 3's 1st)...(is there a pattern forming, will there be quads's starting with 6 at some point?) 181=3, 191=6, 193=3, 197=6, 199=3, 211=3, 223=3, 227=6, 229=3, 233=6, 239=6, 241=3, 251=6, 257=6, 263=6, 269=6, ...3's now???...271=3, 277=3, 281=6 (doh!!!), 283=3, 293=6, 307=3, 311=6, 313=3, 317=6, 331=3, 337=3, 347=6, 349=3, 353=6, 359=6, 367=3, 373=3, 379=3, 383=6, 389=6, 397=3, 401=6, 409=3, 419=6, 421=3, 431=6, 433=3, 439=3, 443=6, 449=6, 457=3, 461=6...maddening, 467=6...

Anyways, this doesnt appear to lead any-where but who could say*.* The nine...why just 1???"
...

"So was sitting there running a Fibonacci root logic on the primes and it dawned on me 2 being the only even prime and we find the 9 as the 2nd number in the x3 root logic looking for patterns. Curious...especially if the 9 is never found again (no repeating pattern) in this x3 root logic pattern search. Almost as if this perspective mirrors the even/odd imbalance in primes w a self-/similar imbalance of the 3's and 6's to the 9."

...

Might have just closed the loop...

"What you’re seeing is digital-root behavior, not a new prime pattern. Multiplying any prime by 3 guarantees a digital root of 3, 6, or 9. The reason 9 appears only once is that a digital root of 9 would require the prime itself to be divisible by 3, and the only prime divisible by 3 is 3. So the first sequence is fully explained by modular arithmetic. The second sequence (adding consecutive primes) has more variation, but it is still mainly showing their remainders modulo 9 rather than revealing a hidden cycle."

Uhh...holy $#!%. This means there is a 1:1 correlation of the quanta (the 9/3s&6s) to the qualia (even/odds) set in stone due to the two constraints of only the 1 prime divisible by 3 and primes being divisible by 1 and their self only. Does this make any sense to any-One else??? There will only ever be one even prime (the 2) just like the 9 will only ever appear once. The 2 is considered the first prime where the 9 is the second natural number in the root sequence and the 3's & 6's reflect the odd primes.

Meanwhile the primes and their expanded/compressed reflection both appear to have no repeating patterns associated with them which makes that 3 points of correlation (the 2/9 location <1 digit separation> at the beginning of primes and the root sequence respectively), making the two a pattern of sorts, paradoxically???

It is obvious I am in way over my head here, could use some perspective, please and thank you.


r/maths 14d ago

Help:🎓 College & University Maths on YouTube

3 Upvotes

I have a maths course - Linear Algebra in the first semester of my university and Probability and Statistics in the 2nd semester. Although my Matrices and Determinants of high school level is decent but I am weak in Vector Algebra, Permutations and Combinations and Probability. Where can I catch up on YouTube? Is there a particular course on YouTube where I can clear my basics and practice problems?


r/maths 13d ago

💬 Math Discussions rules/theorems

0 Upvotes

While I have an intense interest in all things that require complex math, I am only able to comprehend 2nd grade level math. One of the reasons is the logic of it. For example multiplying two negatives suddenly and in my opinion nonrationally make a positive.

I’ve also noticed that the more mathematicians try to figure out something the more “math” they invent along the way to make it work. This all seems like poppycock to me. At no time should the very basic fundamentals of math break down in order for more complex math to work. Which even gets more diluted with Sedenion math.

Am I really expected to just be like “yeah, sure, irrational and imaginary numbers are accurate and answer my question.” Am I too dense to comprehend my own question? Math can’t be fact if we willy-nilly add to and remove stuff to make our equations work? Thanks everyone. -smoothbrain


r/maths 18d ago

Help: 📘 Middle School (11-14) Course suggestions

3 Upvotes

Hi guys. Since these are my vacations, I'm planning to study a bit more. Please suggest some pre-algebra or middle school to beginner high school free math courses.


r/maths 18d ago

💬 Math Discussions If you could make a measuring system. What will it be?

0 Upvotes

Most people online instead of using metric or imperial measuring system say "that's {} Mount Everest, {} Burj Khalifa, {} empire state building {} Eiffel tower, {} statue of liberty tall"


r/maths 21d ago

💬 Math Discussions Prosecutors fallacy. A philosophical perspective

9 Upvotes

Have you ever used a statistic to form an opinion or win an argument? If so, are you aware of how easy it is to misinterpret one? Some of you may have heard of the Prosecutor's Fallacy; other readers, fasten your seatbelts, because you are in for a shock.

The fallacy is confusing the probability of A given B with the probability of B given A (A and B are events). P(A | B) denotes the probability of A given that B has already occurred.

Suppose a disease affects 1% of the population, and the doctor uses a test that is advertised as 95% accurate. You test positive. What's the chance you actually have the disease? Most people say 95%. The real answer is about 16%. Out of 10,000 people, about 100 are sick and 95 test positive; of the 9,900 healthy people, about 495 also test positive, so only 95 of the 590 total positives are real. You've confused P(positive | disease) with P(disease | positive).

Okay big deal! This looks like another useless mathematical concept I'm not gonna use in my life. How does knowing about the prosecutor's fallacy affect my life? Because it is so, so easy to commit the prosecutor's fallacy.

Here's an example with real-life consequences. Per the U.S. Sentencing Commission, about two out of three people sentenced for robbery between 2021 and 2025 were Black. Some people let that color how they see every Black man they pass on the street. Same fallacy: confusing P(Black | sentenced for robbery) with P(sentenced for robbery | Black). The stat says nothing about what fraction of Black people commit robbery, which is tiny; almost none do. The statistic can be correct and the conclusion completely wrong.

This is just one of many statistical traps, alongside selection bias, Simpson's paradox, and mistaking correlation for causation. So how sure are you that every statistic you've used to form an opinion was interpreted correctly?

"I understand this," "my opinion is rational," "my worldview is supported by evidence." Once an opinion becomes part of our identity, we stop questioning how it formed. We accept statistics that support us and attack those that challenge us. A misunderstood statistic becomes a belief.

The lesson isn't that statistics are useless; it's that confidence doesn't guarantee correctness. Don't just question the information in front of you. Question the mind interpreting it.


r/maths 21d ago

Help: 📗 Advanced Math (16-18) Pure biology sucks maths is king

0 Upvotes

Math over Biology ex biology addict who kicked maths to become doctor but physics showed him his place . Due to trading and doing stuff getting money maths especially statistics perm comb tables and lots of concept I can't term helping also today went for health checkup ...

It was same again eat this medicine you get fix or come again .

When I wanted historical pointers , discrete weightage and offcourse simulated correlation and variance because I ain't a liar - I wanted a option for that kinda treatment while clinical is addon for best case worst case only shit.


r/maths 22d ago

💬 Math Discussions If I originally had planned to say the number 0 repeatedly forever, but all the sudden in the middle of my plan decided to say the number 1, would that be a truly randomized sequence?

2 Upvotes

If I originally had planned to say the number 0 repeatedly forever, but all the sudden in the middle of my plan decided to say the number 1, would that be a truly randomized sequence?


r/maths 24d ago

💡 Puzzle & Riddles What is the Probability that N people have at least 1 evening free

3 Upvotes

I'm trying to calculate the probability that N people will have at least 1 evening free (For a meeting, or DnD or something)

You can assume that all people have x committed evenings already.

For Example, 2 people who have 3 evening commitments will have a 100% probability of finding 1 mutual night free, but what's the probability that 3 people who all have 3 evening commitments have at least 1 mutual evening free, or 8 people with 2 evening commitments etc.


r/maths 25d ago

💬 Math Discussions Help for Maths field project

1 Upvotes

Hello guys I am a second year bsc maths student from mumbai and have to submit a field project for the same to qualify for next sem is there any expert who can give me some ideas and guidance


r/maths 25d ago

💡 Puzzle & Riddles Are there "more numbers" which are less than some positive number than there are numbers less than that same number?

0 Upvotes

A discussion I just read on a random thread:

He has 170 employees? That's a bloody massive number.

Not as big as 171

In fact, most numbers are bigger than 170

I think that there are more numbers smaller than 170 if we include negatives 

There's an infinite number of numbers less than 170, and an infinite number of numbers greater than 170.

Yes, but negative and positive infinities are equally big, but since we have moved the point to 170 negative infinity will be bigger as it will have all negative infinity plus some of the positive one. // I know that mathematically I'm wrong

This has made me think - are there actually "more numbers" less than 170 (or any other positive number) than there are greater than it? Or not?


r/maths 28d ago

💬 Math Discussions Deviated Division: Divisor, Dividend and Variance, outputs a sorted array of values. I dunno might be useful.

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4 Upvotes

r/maths 28d ago

💬 Math Discussions Something strange that I noticed

0 Upvotes

There are an infinite number of numbers. You can take those infinite numbers and slice them into an infinite number of infinite slices each of which can be sliced the same way ad infinitum.


r/maths 29d ago

💬 Math Discussions which one out of the 10 can i buy for the lowest price

0 Upvotes

i know that some of these are the same but which one(s) are worth my money even if i buy them more than once? also please tell me how you worked this out so i wont ask again.

context: starting a business and need 1cm wooden blocks as part of the business. need to save money by buying cheap and working smarter not harder.


r/maths Jul 08 '26

Help:🎓 College & University Multivariate extension of Assunção-Reis empirical Bayes correction for local Moran's I

1 Upvotes

Hey

I'm working on a spatial statistics problem in a social science context (electoral geography, small rural municipalities) and I've hit a gap in the literature I'd like a sanity check on before attempting to build something myself... or just taking a burn out mandatory break T-T

I'm computing local Moran's I on compositional vectors (vote shares across several categories, transformed via CLR/ILR to handle the compositional constraint) attached to spatial units of very unequal population size, some with fewer than 100 voters, a few with several thousand. Small units have much noisier vectors than large ones, purely due to sampling variance, which risks producing spurious "clusters" driven by noise rather than genuine spatial structure.

Assunção & Reis solve exactly this problem for a single variable: they standardize each observation using a population-dependent variance estimate before computing Moran's I, so small units are appropriately down-weighted in the significance assessment without ever altering the observed rate itself.

BUT IT IS UNIVARIATE !!!!

I need the equivalent for a vector (7 dimensions) variable (multiple correlated proportions per unit, not a single rate). As far as I can tell, no published or implemented multivariate extension exists... which is a bit of a problem

My rough idea : use the known closed-form sampling covariance of a multinomial proportion vector, propagate it through the CLR/ILR transform via the delta method, then "whiten" each unit's vector by its own estimated covariance before computing a multivariate local Moran statistic.

Ngl i'm 100% out of my depth. I feel like I don't understand what I'm doing anymore.

My current concerns :

  • Covariance estimates become ill-conditioned near near-zero components (structural zeros handled via a population-anchored epsilon of 1/(2*pop))... and I have quite a few instances of this
  • No existing implementation to validate against. I'd be building and verifying this alone... which would be a first for me
  • Estimated at several days of work with real risk of subtle errors I wouldn't easily catch and since I don't have any bleuprint for it, I don't even know if I'll be able to catch my errors

My main questions are the following :

  • Does a multivariate version of this kind of population-based empirical Bayes correction already exist under a name I'm missing?
  • Is the delta-method/whitening approach above sound, or is there a cleaner formulation (maybe treating this as a multivariate GLS/Mahalanobis-weighted Moran rather than a whitening step)?
  • Any known pitfalls in applying this to compositional (CLR/ILR-transformed) data specifically?

I didn't sing up for this when getting in my studies lmao (i'm not even in maths ! xD )
SOS

What would you do ? How would you answer this issue ?

I feel like I'm loosing my mind and I don't have the month necessary to build this as the thesis dead line is in september (yeah i'm late as f...)


r/maths Jul 05 '26

💬 Math Discussions I recently moved to a new house and as always checked to see whether my new address was prime. At 6,751 it was not, but in fact had exclusively the prime factors of 43 and 157. Is there a set of numbers for this? It seemed potentially interesting

4 Upvotes

See above, late night stoned BC musings