r/learnmath

There are 400 stickers in a complete set. I have 390 so am 10 away from completing the set. I have 250 chances (stickers to randomly draw) what are the odds or percentage or the amount of cards drawn that I need?

A relation R ={(a,b): a is wife of y} is a relation which is not Reflexive nor symmetric but it is transitive and trivially Transitive so kindly help in understanding how trivially transitivity works in this case or in general.

I am currently studying Pre-Calculus and Calculus on my own and was hoping someone might have a suggestion for a textbook or book that might help me learn the subject better. I am not looking for an extremely difficult text, nor do I wish to read something too simplistic like “Calculus for Kids.” Instead, I am seeking something that is easy to read yet structured.

Hello, i want to compare two medians and quantify the difference if it is a large, small, or minimal change. Would I do this by dividing the difference of the medians by the standard deviation?

If not, how do I know if the difference between medians and meaningful or not. Not looking for P values, but will it be necessary?

could someone please explain how you would get y here: 2x - 4y = 12 (x is -2)

i’m really stumped

I’m filling out a course registration questionnaire for my college (I’m a rising college freshman) and they are asking what the highest math course I’ve taken is. My junior year I took honors algebra two but my senior year I did not take pre-calculus and instead took a statistics and probability class. Which one is considered the higher math course?

Hi everyone,

Today, I learned that the complex numbers are not the largest possible number system. It turns out there are many other number systems beyond them, such as octonions and sedenions! I actually learned this from my esteemed mathematics teacher, Mustafa Yağcı.

My question is: Are there any good resources (books, lecture notes, or papers) written in either English or Turkish where I can study hypercomplex numbers? Also, where can I obtain or purchase them?

Thanks in advance for your recommendations!

For context, I am a pure math major with preliminary knowledge in Group Theory, Ring Theory, and other such disciplines (especially in a discrete/finite context). I also have a modicum of understanding of Set Theory (including Axiomatic ZFC), but absolutely no training in Topology.

Out of curiosity and a love for abstraction, I wanted to learn Category Theory, so I've done quite a bit of surveying the subject (on wikipedia and nlab mostly). However, I know that in order to be able to use the concepts I need a more formal learning. What progression would y'all recommend for me?

Addition and multiplication usually start feeling familiar after enough practice, but division seems different somehow.

A lot of students can get through the steps, yet still hesitate while solving even simple division questions on their own.

It’s interesting because the difficulty often doesn’t look computational — it looks more like uncertainty about what the numbers actually represent during the process.

I’ve always wondered why division feels mentally “heavier” for so many learners compared to other operations.

I'm looking for two functions Q -> Z such that gcd(num(x), den(x)) = 1 and num(x)/den(x) = x. So, num(0.5) = 1, and den(0.5) = 2. I assume it will be an infinite series, but can't find anything online because it all just brings up elementary "what is a fraction" articles.

Edit: Here is the solution: https://www.reddit.com/r/learnmath/s/nkH0H0eaBv

hello there.

I am currently in 10th grade. I'm currently in sem 2 (ontario canada btw), and I find my my situation quite perplexing. I find that I understand and am very fundamentally strong at math, but whenever tests come up, I just bomb the frick outta them and am performing quite bad tbh. I'm not sure though, it seems impossible to improve. I've gotten too many people saying to do contest questions or high amounts of practice. Well, I've been doing that, but no results seem to come. It's even more frustrating given that i had to work my ahh off to pull up a comeback in my later years of middle school, as I wasn't naturally studious. Ib has truly been a reality check. I also want to pursue engineering in the future, and it seems like a huge gamble that I took real ib next year, and I'm extremely scared and nervous. Has anyone else gone through a similar situation? Thanks so much.

I’m looking for a serious math tutor/mentor.

I’m 19 and currently trying to rebuild my mathematical foundation from the ground up with the long-term goal of becoming highly competent in mathematics, physics, computer science, and engineering-related fields.

I’ve been self-studying for a while, but I’ve realised that doing this completely alone is becoming inefficient.

I struggle with accountability, direction, and knowing whether I’m progressing correctly. I also think years of frustration and failure around maths have affected my confidence and consistency more than I’d like to admit.

What I’m looking for:

• Someone with strong mathematical ability (Olympiad background or very strong problem-solving experience would be ideal)
• Comfortable teaching undergraduate-level mathematics
• Able to provide challenging problems, good resources, and structured guidance
• Someone who values deep understanding and mathematical thinking, not just memorising procedures

I’m not looking for shortcuts or surface-level motivation. I genuinely want to become good at this, even if it takes years of work.

I currently work full-time warehouse shifts, and outside work, I spend most of my time studying maths.

Right now I feel like I’m at a fork in the road. I can either continue drifting and making slow, inconsistent progress alone or finally get proper guidance and build real momentum.

If this sounds like something you could help with, feel free to DM me with your background, experience, and teaching approach.

Thank you so much for your time!

(x•x+x) / x = 10

My logic

(x^2 + x) / x = 10

(x^2 / x) + ( x / x ) = 10

x + 1 = 10

x = 9

for context, im a highschool senior, and i find highschool math really fun and easy. but the most challenging part that i have ran into is multiplying 2 matrices, i just keep forgetting what to do and how to and then i stop trying to figure out where to put the number i found out in the new matrix.

I’ve noticed that some students can solve calculations quite comfortably during practice, but the moment the same concept appears inside a paragraph or “real-life situation,” they become unsure very quickly.

For example, a student may solve fraction operations correctly on their own, but struggle to identify what the question is actually asking in a word problem.

It makes me wonder whether the difficulty is more about mathematical reasoning, reading comprehension, or simply anxiety caused by longer questions.

Has anyone else experienced this while learning or teaching Maths?

do students suddenly struggle when numbers are inside word problems?

I have got a basic idea of differential equations , where on yt can I expand more of my knowledge like ODE, PDE and modelling.

2 complex numbers z=x+iy be compared with < > =?

does z1>z2 make sense

eg. 5+i5>5-i5

Hi, I'm in 10th grade in France and I have a question regarding the calculation of the inter. My teacher gave me the calculation for the union:

p(AuB)=p(A)+p(B)-p(AnB)

On that point I have no problem

But he didn't give us the calculation for the interchange. And I spoke with several people and they told me:

p(AnB)=p(A)×p(B) Or p(AnB)=p(A)+p(B)-p(AuB)

I'm not very good at math, but normally it should be the same result, but of course not.

because sometimes we need to calculate the intersection but we don't have the union and if we want to calculate the union we can't because we don't have the intersection we're looking for.

Thank you for explaining.