ka May Highlights and 2025 AoPS Online Class Information
jlacosta0
May 1, 2025
May is an exciting month! National MATHCOUNTS is the second week of May in Washington D.C. and our Founder, Richard Rusczyk will be presenting a seminar, Preparing Strong Math Students for College and Careers, on May 11th.
Are you interested in working towards MATHCOUNTS and don’t know where to start? We have you covered! If you have taken Prealgebra, then you are ready for MATHCOUNTS/AMC 8 Basics. Already aiming for State or National MATHCOUNTS and harder AMC 8 problems? Then our MATHCOUNTS/AMC 8 Advanced course is for you.
Summer camps are starting next month at the Virtual Campus in math and language arts that are 2 - to 4 - weeks in duration. Spaces are still available - don’t miss your chance to have an enriching summer experience. There are middle and high school competition math camps as well as Math Beasts camps that review key topics coupled with fun explorations covering areas such as graph theory (Math Beasts Camp 6), cryptography (Math Beasts Camp 7-8), and topology (Math Beasts Camp 8-9)!
Be sure to mark your calendars for the following upcoming events:
[list][*]May 9th, 4:30pm PT/7:30pm ET, Casework 2: Overwhelming Evidence — A Text Adventure, a game where participants will work together to navigate the map, solve puzzles, and win! All are welcome.
[*]May 19th, 4:30pm PT/7:30pm ET, What's Next After Beast Academy?, designed for students finishing Beast Academy and ready for Prealgebra 1.
[*]May 20th, 4:00pm PT/7:00pm ET, Mathcamp 2025 Qualifying Quiz Part 1 Math Jam, Problems 1 to 4, join the Canada/USA Mathcamp staff for this exciting Math Jam, where they discuss solutions to Problems 1 to 4 of the 2025 Mathcamp Qualifying Quiz!
[*]May 21st, 4:00pm PT/7:00pm ET, Mathcamp 2025 Qualifying Quiz Part 2 Math Jam, Problems 5 and 6, Canada/USA Mathcamp staff will discuss solutions to Problems 5 and 6 of the 2025 Mathcamp Qualifying Quiz![/list]
Our full course list for upcoming classes is below:
All classes run 7:30pm-8:45pm ET/4:30pm - 5:45pm PT unless otherwise noted.
Introduction to Algebra A
Sunday, May 11 - Sep 14 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Wednesday, May 14 - Aug 27
Friday, May 30 - Sep 26
Monday, Jun 2 - Sep 22
Sunday, Jun 15 - Oct 12
Thursday, Jun 26 - Oct 9
Tuesday, Jul 15 - Oct 28
Introduction to Counting & Probability
Thursday, May 15 - Jul 31
Sunday, Jun 1 - Aug 24
Thursday, Jun 12 - Aug 28
Wednesday, Jul 9 - Sep 24
Sunday, Jul 27 - Oct 19
Introduction to Number Theory
Friday, May 9 - Aug 1
Wednesday, May 21 - Aug 6
Monday, Jun 9 - Aug 25
Sunday, Jun 15 - Sep 14
Tuesday, Jul 15 - Sep 30
Introduction to Algebra B
Tuesday, May 6 - Aug 19
Wednesday, Jun 4 - Sep 17
Sunday, Jun 22 - Oct 19
Friday, Jul 18 - Nov 14
Introduction to Geometry
Sunday, May 11 - Nov 9
Tuesday, May 20 - Oct 28
Monday, Jun 16 - Dec 8
Friday, Jun 20 - Jan 9
Sunday, Jun 29 - Jan 11
Monday, Jul 14 - Jan 19
Paradoxes and Infinity
Mon, Tue, Wed, & Thurs, Jul 14 - Jul 16 (meets every day of the week!)
Intermediate: Grades 8-12
Intermediate Algebra
Sunday, Jun 1 - Nov 23
Tuesday, Jun 10 - Nov 18
Wednesday, Jun 25 - Dec 10
Sunday, Jul 13 - Jan 18
Thursday, Jul 24 - Jan 22
MATHCOUNTS/AMC 8 Basics
Friday, May 23 - Aug 15
Monday, Jun 2 - Aug 18
Thursday, Jun 12 - Aug 28
Sunday, Jun 22 - Sep 21
Tues & Thurs, Jul 8 - Aug 14 (meets twice a week!)
MATHCOUNTS/AMC 8 Advanced
Sunday, May 11 - Aug 10
Tuesday, May 27 - Aug 12
Wednesday, Jun 11 - Aug 27
Sunday, Jun 22 - Sep 21
Tues & Thurs, Jul 8 - Aug 14 (meets twice a week!)
AMC 10 Problem Series
Friday, May 9 - Aug 1
Sunday, Jun 1 - Aug 24
Thursday, Jun 12 - Aug 28
Tuesday, Jun 17 - Sep 2
Sunday, Jun 22 - Sep 21 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Monday, Jun 23 - Sep 15
Tues & Thurs, Jul 8 - Aug 14 (meets twice a week!)
AMC 10 Final Fives
Sunday, May 11 - Jun 8
Tuesday, May 27 - Jun 17
Monday, Jun 30 - Jul 21
AMC 12 Problem Series
Tuesday, May 27 - Aug 12
Thursday, Jun 12 - Aug 28
Sunday, Jun 22 - Sep 21
Wednesday, Aug 6 - Oct 22
Introduction to Programming with Python
Thursday, May 22 - Aug 7
Sunday, Jun 15 - Sep 14 (1:00 - 2:30 pm ET/10:00 - 11:30 am PT)
Tuesday, Jun 17 - Sep 2
Monday, Jun 30 - Sep 22
Some users don't want to learn, some other simply ignore advises.
But please follow the following guideline:
To make it short: ALWAYS USE YOUR COMMON SENSE IF POSTING!
If you don't have common sense, don't post.
More specifically:
For new threads:
a) Good, meaningful title:
The title has to say what the problem is about in best way possible.
If that title occured already, it's definitely bad. And contest names aren't good either.
That's in fact a requirement for being able to search old problems.
Examples: Bad titles:
- "Hard"/"Medium"/"Easy" (if you find it so cool how hard/easy it is, tell it in the post and use a title that tells us the problem)
- "Number Theory" (hey guy, guess why this forum's named that way¿ and is it the only such problem on earth¿)
- "Fibonacci" (there are millions of Fibonacci problems out there, all posted and named the same...)
- "Chinese TST 2003" (does this say anything about the problem¿) Good titles:
- "On divisors of a³+2b³+4c³-6abc"
- "Number of solutions to x²+y²=6z²"
- "Fibonacci numbers are never squares"
b) Use search function:
Before posting a "new" problem spend at least two, better five, minutes to look if this problem was posted before. If it was, don't repost it. If you have anything important to say on topic, post it in one of the older threads.
If the thread is locked cause of this, use search function.
Update (by Amir Hossein). The best way to search for two keywords in AoPS is to input
[code]+"first keyword" +"second keyword"[/code]
so that any post containing both strings "first word" and "second form".
c) Good problem statement:
Some recent really bad post was:
[quote][/quote]
It contains no question and no answer.
If you do this, too, you are on the best way to get your thread deleted. Write everything clearly, define where your variables come from (and define the "natural" numbers if used). Additionally read your post at least twice before submitting. After you sent it, read it again and use the Edit-Button if necessary to correct errors.
For answers to already existing threads:
d) Of any interest and with content:
Don't post things that are more trivial than completely obvious. For example, if the question is to solve , do not answer with " is a solution" only. Either you post any kind of proof or at least something unexpected (like " is the smallest solution). Someone that does not see that is a solution of the above without your post is completely wrong here, this is an IMO-level forum.
Similar, posting "I have solved this problem" but not posting anything else is not welcome; it even looks that you just want to show off what a genius you are.
e) Well written and checked answers:
Like c) for new threads, check your solutions at least twice for mistakes. And after sending, read it again and use the Edit-Button if necessary to correct errors.
To repeat it: ALWAYS USE YOUR COMMON SENSE IF POSTING!
Everything definitely out of range of common sense will be locked or deleted (exept for new users having less than about 42 posts, they are newbies and need/get some time to learn).
The above rules will be applied from next monday (5. march of 2007).
Feel free to discuss on this here.
I spent my evening after school, packing for the trip, using the checklist given by my coach.
I didn’t do much preparation, as I was mostly chilling out for the upcoming days.
I also played basketball with my cousin, Kevin, who met Gotham Chess and stayed at his home!
Saturday, May 10th
I woke up at 5:30 AM, ate a light breakfast, and headed out to the airport with my luggage.
I met my teacher, but was surprised that Archishman split up with his own family.
Waiting for the TSA was pretty boring, but we soon got through, and after I found our gate.
A couple of minutes pass by, as I review an AOPS mock where I meet Archischman;
Afterward, we chill out, watch the rube goldberg machine in the airport, and wait to board the plane.
During the plane ride, I played games; however, during our descent, I heard a loud crack, and our plane started wobbling, and we heard cracking sounds in the seats. Fortunately, we were able to land and were able to attend the competition the next day.
After this, heading out, we went to the shuttle; however, we had 35 minutes. We tried to solve the Jane Street card puzzle but failed, and ended up socializing.
After we arrived at the hotel, we received a MASSIVE amount of stuff, like calculators, shirts, coupons, plaques, stickers, etc.
I also saw and got a signature from Richard Rusczyk, which was really cool.
Then, we went to a restaurant named “Chinatown Garden”, with the worst food I’ve ever had.
We then chilled in our rooms, studied for a bit, and started organizing plans for pin trading.
Our goal was to scam as many people as possible by doing 2:1 trades, as we had a “limited”
amount of pins. (We even got 5:1 and 10:1 trades)
A Virginia kid scammed me with a STEM pin, so I chased him down and got our pin back.
We got through around half the states organizing in and out of what pins we had.
Finally, we got some food from the buffet (which was surprisingly decent) and had a good time trading some more.
We ended the day with a short and brief CDR, where we had some fun, and then we went to sleep to anticipate the next day.
At night, I showered and sang karaoke with Archi.
Sunday, May 11th
Getting ready, I found out that a mock (outside the box) was recently released and took it through breakfast.
Then, once we got there at 8:30, there was a mob of parents taking pictures, and music played.
Then every team did introductions/attendance and their chants, most of which were really cringe.
I took the test; however was too slow on the sprint round and got a predicted 16.
On the target round, I was able to get through and got a 12, despite barely not solving p8 to my frustration.
Team round we did decently, scoring a 14/20, which was one of the best scores around us, that even orz states like Texas and Washington didn’t beat.
I predicted around a 28 with the answer key.
After this, we teamed up with North Carolina (chill af) and went to a pho shop (54 Restaurant), which tasted amazing. (A far contrast from Chinatown Garden)
Then, we went to an aerospace museum, where we played Brawl Stars and went around. Eventually, we saw models of blackholes and air vacuums, and played a flight simulator.
Then we went to our hotel, chilled, and watched basketball games.
After, we went to an Indian restaurant named “Himilayan Doko” which was really delicious!
Then we raided different rooms, from NC, HAWAII, Idaho, Virgin Islands, and accidentally a random dudes room who was ticked at us.
Finally, we chilled and went to sleep, though I tried to get Henry and Archi to sleep since they were being annoying.
Monday, May 12th
We start the day forming my pin badge, and then we went to get some breakfast.
After that, we met in the breakfast area with 2 teams for table, and I actually got a 10:1 pin trade which was pretty cool.
After that, we lined up and got our thunderstick/clapping machines, and ran through the entrance of the CDR.
Sadly, we didn’t win anything, but it was cool seeing the results.
Then, we started to watch the CDR, which was really exciting.
It got really interesting when everyone saw Nathan Liu cook his opponent in half a second.
In the semifinals, it was insane, and Advait and Nathan, buzzed every question that was around mid-sprint level.
Then, it finished with Nathan beating Brandon with a 2-second solve, absolute insanity.
Finally, we went back to our rooms and got lunch in the hotel.
A few hours later, we received our scores, and I had bombed, scoring a 26 with 7 sillies. (ouch)
Unfortunately, my teammates Henry and Archishman sillied a bunch of questions.
After, we played Brawl Stars, and went to explore the hotel, where we went up a random staircase and got stuck. We went to the roof, but got scared and yelled out for help on the gym floor. Thankfully, we got back, and I went and reviewed the test.
After we reviewed the test, and went to the Mathcounts Party.
The food was mid, but the games were pretty fun.
We met a bunch of people, played air hockey, foosball, and basketball, while listening to the not so great music in the background.
Then we went back to our rooms at 8PM, to put our pins on, and I got 38/56!
Finally, we met up in a room with a bunch of Cali, and NC kids, and talked about the test, the people, and played Brawl Stars. Even Josh Frost came up to us and asked us how the trip was.
Tuesday, May 13th
I started the day waking up at 6:20, and packed up and ate breakfast. After that, Henry was late, so we packed food for him and went to the bus shuttle.
Eventually, we arrived at the airport, went through security (which was suspiciously fast), and played Brawl Stars. We also ate five guys fries, which was pretty good. Eventually, we had to part our ways with Henry and headed out to our flights, which marked the end of the trip.
Conclusion:
Although we didn’t do amazingly well in the contest, going to DC was an amazing experience. I got to meet people who were passionate about math, and hang out with them, goofing around.
This was the best math contest experience that I’ll likely ever have, and I’m glad I went through it.
In King Arthur's court every knight is friends with at least other knights where friendship is mutual. Prove that King Arthur can place some of his knights around a round table in such a way that every knight is friends with the people adjacent to him and between them there are at least friendships of knights that are not adjacent to each other.
Problem. Let a,b,c be three positive real numbers with a+b+c=3. Prove that \color{blue}{\frac{1}{4a^{2}+9}+\frac{1}{4b^{2}+9}+\frac{1}{4c^{2}+9}\le \frac{3}{abc+12}.}
When does equality hold?
P/s: Could someone please convert it to latex help me? Thank you!
Let be a positive integer. We say that a positive integer is -good if is divisible by for all positive integers with . Suppose is a positive integer such that is -good, but is not -good. Prove that is prime.
My favorite problems on the state test were target #6 and sprint #29. I loved the aha moment when I saw pascal's triangle on target #6, and even though I got sprint #29 wrong due to a long division error, it was so much fun to use the sum of the factors trick to find the right answer!
Also: My score was 29 with 12 on target and 17 (sad sillies) on sprint, so I didn't make CDR
This post has been edited 1 time. Last edited by Ljviolin11, Apr 1, 2025, 3:03 PM
let the legs of the triangle be and . Then we have Additionally, by the triangle inequality, we know the hypotenuse is less than , and because it is the longest side, it is greater than Also, because the question simply asks for the length of the hypotenuse without "simplest radical form" or "common fraction" at the end of the problem, we know the hypotenuse is an integer. Thus, the only numbers that can be the length of the hypotenuse are ,,,,, and . Plugging values into the equation in line yields
let the legs of the triangle be and . Then we have Additionally, by the triangle inequality, we know the hypotenuse is less than , and because it is the longest side, it is greater than Also, because the question simply asks for the length of the hypotenuse without "simplest radical form" or "common fraction" at the end of the problem, we know the hypotenuse is an integer. Thus, the only numbers that can be the length of the hypotenuse are ,,,,, and . Plugging values into the equation in line yields
bruh even worse sol, calc bash and guess based on answer form
; a^2+b^2=c^2 and a+b = 40-c. Square the second equation. a^2+b^2+2ab=1600+c^2-80c. Cancel out a^2+b^2 and c^2 from both sides since they are equivalent. 2ab = 1600-80c. In the problem we are given that ab/2 = 20 so 2ab=80. Now 1600-80c=80 or c=19.
I randomly added up all the squares from 1 to 2025 and divided that by the sum of all integers 1-2025 (I don't even know why) and somehow got the right answer after doing a bunch of random other things.
This post has been edited 1 time. Last edited by chesswillow, Apr 25, 2025, 3:27 PM
I randomly added up all the squares from 1 to 2025 and divided that by the sum of all integers 1-2025 (I don't even know why) and somehow got the right answer.
I used a method kind of guessing but we can see the number of subsets that have 2025 as the greateset is (Not Blank)
2^2025-1
Then the number of subsets that have 2024 as the greatest is:
2^2024 -1
Then the numbers of subsets that have 2023 as the greatest is:
2^2023-1
We establish a pattern similar to an geometric sequence but not exact.... 1/2, 1/4, 1/8, 1/16, 1/32,1/64,1/128,1/256 So with this pattern we already know that the numbers that count the most are the first 3 numbers that I listed but if you look at it carefully you can see that when you subtract some integer n from n_1+n_2 we see what it is always 1/2^n so we can use this finding to see that is has to be somewhere between 2024>=x>=2023
but we again see that 1/4-1/8=1/8 so we are done and our final answer is
This post has been edited 1 time. Last edited by sadas123, Apr 5, 2025, 11:09 AM
Add one set with just element 0.
First two sets have average 1/2
Average with two sets of average 2 makes four sets with average 1+1/4
Average with four sets of average 3 makes eight sets with average 2+1/8
...
average is 2024 + 1/ 2^2025,
not needed but you can adjust by removing 0 set to get exact average