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k a March Highlights and 2025 AoPS Online Class Information
jlacosta   0
Mar 2, 2025
March is the month for State MATHCOUNTS competitions! Kudos to everyone who participated in their local chapter competitions and best of luck to all going to State! Join us on March 11th for a Math Jam devoted to our favorite Chapter competition problems! Are you interested in training for MATHCOUNTS? Be sure to check out our AMC 8/MATHCOUNTS Basics and Advanced courses.

Are you ready to level up with Olympiad training? Registration is open with early bird pricing available for our WOOT programs: MathWOOT (Levels 1 and 2), CodeWOOT, PhysicsWOOT, and ChemWOOT. What is WOOT? WOOT stands for Worldwide Online Olympiad Training and is a 7-month high school math Olympiad preparation and testing program that brings together many of the best students from around the world to learn Olympiad problem solving skills. Classes begin in September!

Do you have plans this summer? There are so many options to fit your schedule and goals whether attending a summer camp or taking online classes, it can be a great break from the routine of the school year. Check out our summer courses at AoPS Online, or if you want a math or language arts class that doesn’t have homework, but is an enriching summer experience, our AoPS Virtual Campus summer camps may be just the ticket! We are expanding our locations for our AoPS Academies across the country with 15 locations so far and new campuses opening in Saratoga CA, Johns Creek GA, and the Upper West Side NY. Check out this page for summer camp information.

Be sure to mark your calendars for the following events:
[list][*]March 5th (Wednesday), 4:30pm PT/7:30pm ET, HCSSiM Math Jam 2025. Amber Verser, Assistant Director of the Hampshire College Summer Studies in Mathematics, will host an information session about HCSSiM, a summer program for high school students.
[*]March 6th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar on Math Competitions from elementary through high school. Join us for an enlightening session that demystifies the world of math competitions and helps you make informed decisions about your contest journey.
[*]March 11th (Tuesday), 4:30pm PT/7:30pm ET, 2025 MATHCOUNTS Chapter Discussion MATH JAM. AoPS instructors will discuss some of their favorite problems from the MATHCOUNTS Chapter Competition. All are welcome!
[*]March 13th (Thursday), 4:00pm PT/7:00pm ET, Free Webinar about Summer Camps at the Virtual Campus. Transform your summer into an unforgettable learning adventure! From elementary through high school, we offer dynamic summer camps featuring topics in mathematics, language arts, and competition preparation - all designed to fit your schedule and ignite your passion for learning.[/list]
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0 replies
jlacosta
Mar 2, 2025
0 replies
J
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9 Pi or Tau
jkim0656   82
N 14 minutes ago by Charizard_637
Hey Aops!
Pi = Circumfrence/Diameter
Tau = Circumfrence/Radius
I have noticed a lot of sites, including Khan Academy, in support of tau over pi...
so what do you think?
https://www.scientificamerican.com/article/let-s-use-tau-it-s-easier-than-pi/
However i am still in support of the good ol pi :)
(btw this is my first aops poll) :-D

EDIT: 50 votes!!! :play_ball:
EDIT: 100 votes!!! :jump:
EDIT: 150 votes! :trampoline:
EDIT: 200 votes! ;)
Edit: 250 votes !!!! yaya :gathering:

If u support pi pls upvote :)
82 replies
jkim0656
Mar 14, 2025
Charizard_637
14 minutes ago
J
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Is your state listed?
Chatelet1   366
N 22 minutes ago by Oshawoot
Multiple states have announced their top students who will advance to the 2025 MATHCOUNTS National Competition in May:

• From Alabama: Henry Gladden of Mobile, Austin Lu of Birmingham, Jessie Shi of Vestavia, and Minlu Wang-He of Auburn.

• From Arkansas: Ryan Fan of Fayetteville, Vivek Kalyankar of Fayetteville, Evan Ning of Fayetteville and Charles Yao of Conway.

• From Connecticut: Hayden Hughes of Newtown, Ethan Shi of Riverside, Alex Svoronos of Greenwich and Elaine Zhou of Hamden.

• From the Department of Defense: Narmin Guliyeva of Ankara, Turkey; Taeyul Kim of Manana, Bahrain; Nathan Liang of Wiesbaden, Germany; and Lucas Sze of Okinawa, Japan.

• From Hawaii: Taehwan Jeon, Hilohak Kwak, Isaac Qian and Thien Tran, all from Honolulu.

• From Kansas: Haidan Anderson & Jayden Xue of Overland Park, Christopher Spencer of Manhattan, and Ruby Jiang of Lawrence.

• From Maine: Ana Kanitkar & Connor Kirkham of Falmouth, Anna McClary of Hermon and Poppy Sandin of Bar Harbor.

• From Massachusetts: Eric Huang of Acton, Shlok Mukund & Brandon Ni of Lexington, and Soham Samanta of Medford.

• From Missouri: Lucas Lai of Columbia, Kevin Shi of St. Louis, Charles Yong & Jay Zhou of Chesterfield.

• From Montana: Titus Gilder of Missoula, Otis Heggem of Billings, Kaleb Houtz of Great Falls and Evan Newcomer of Missoula.

• From Nevada: Solomon Dumont of Las Vegas, Aaron Lei of Reno, Leeoz Nebat of Henderson and Maxwell Tsai of Las Vegas.

• From New Mexico: Mark Goldman, Daniel He, Iris Huang and Patrick McArdle, all from Albuquerque.

• From New York: Derrick Chen of Great Neck, Victor Yang of Great Neck, Hanru Zhang of Jericho and Ryan Zhang of Jericho.

• From Rhode Island: Kahlan Anderson of the Wheeler School, Julian Bernhoft & Colin Hegstrom of Providence, and Theodora Watson of Barrington.

• From South Carolina: Yukai Hu of Elgin, Justin Peng of Clemson, Geonhoo Shim of Columbia, and Aaron Wang of Mount Pleasant.

• From South Dakota: Seth Chaplin & Maxwell Wang of Sioux Falls, Laukia Gundewar of Aberdeen, and Cohwen Heimann of Aberdeen.

• From Texas: Shaheem Samsudeen & Ayush Narayan of Plano, Nathan Liu of Richardson, and James Stewart of Southlake.

• From Vermont: Mohid Ali of South Burlington, Vivek Chadive of South Burlington, Joshua Kratze of St. Johnsbury and Albert Zhang of South Burlington.

• From Wisconsin: August Reeder & Lucy Chen of Fitchburg, Junhao Feng of Milwaukee, and Jiyan Singh of River Hills.

===
Updated on 3/15/2025:

• From Colorado: Noah Liu, Christopher Zhu, Neo Luo, and Andrew Zhao.

• From Florida: Arnav Bhatia, Gnaneswar Peddesugari, Edwin Gao, and Rananjay Parmar.

• From Indiana: Roland Li, Hrishabh Bhowmik, Sophia Chen, and Arjun Raman.

• From Kentucky: Sri Shubhaan Vulava, Joyce Liu, Victor Gong, and Brandon Tedja.

• From Maryland: Eric Xie, Angie Zhu, Roger Huang, and Leo Su.

• From Michigan: Arnav Vunnam, Eric Jin, Akshaj Malraj, and Chaithanya Budida.

• From Minnesota: Ahmed Ilyasov, Will Masanz, Anshdeep Singh, and Branden Qiao.

• From New Jersey: Ethan Imanuel, Advait Joshi, Jay Wang, and Easton Wei.

• From North Carolina: Shivank Chintalpati, Steven Wang, Lucas Li, and Leo Hong.

• From Ohio: Henry Lu, Andy Mo, Archishmen Dey, and Caleb Tan.

• From Oregon: Sophia Han, Kevin Cheng, Garud Shah, and Ryan Zhang.
366 replies
Chatelet1
Mar 8, 2025
Oshawoot
22 minutes ago
J
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MATHCOUNTS State Preparation
mithu542   23
N an hour ago by Bnn81351
Hello!

I'm going to prepare for Mathcounts state soon. I want some advice on what to do. I am in 7th grade, and I want to make it to nationals. I know I should obviously take practice tests, but should I do something else other than that, or just grind all (or most) practice tests from previous years? Also, how much should I focus on Countdown round relative to the other tests?

(For reference, I got 43 on school, and 41 on chapter. Last year, I got 16/116 rank in state. Since then, I have done the following courses from aops:
Intro: algebra b, number theory, c&p, geometry
Intermediate: algebra, number theory, c&p)
23 replies
mithu542
Feb 14, 2025
Bnn81351
an hour ago
J
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Problem of the week
evt917   23
N 3 hours ago by DearPrince
Whenever possible, I will be posting problems twice a week! They will be roughly of AMC 8 difficulty. Have fun solving! Also, these problems are all written by myself!

First problem:

$20^{16}$ has how many digits?
23 replies
evt917
Mar 5, 2025
DearPrince
3 hours ago
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No more topics!
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Cutting Cheese
mithu542   5
N Yesterday at 1:25 AM by ohiorizzler1434
A cube of cheese $C=\{(x,y,z)|0\le x,y,z\le 1\}$ is cut along the planes $x=y, y=z$, and $z=x$. How many pieces are there? (No cheese is moved until all three cuts are made.)

sol confirmation
5 replies
mithu542
Feb 28, 2025
ohiorizzler1434
Yesterday at 1:25 AM
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Cutting Cheese
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mithu542
1555 posts
mithu542
#1 h  Feb 28, 2025, 3:25 PM
Y by
A cube of cheese $C=\{(x,y,z)|0\le x,y,z\le 1\}$ is cut along the planes $x=y, y=z$, and $z=x$. How many pieces are there? (No cheese is moved until all three cuts are made.)

sol confirmation
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Math-lover1
67 posts
Math-lover1
#2 h  Mar 12, 2025, 4:32 AM
Y by
I think if you sort of draw it out you can label the different sections
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oinava
506 posts
oinava
#3 h  Saturday at 11:54 PM
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sol
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ohiorizzler1434
696 posts
ohiorizzler1434
#4 h  Yesterday at 12:00 AM
Y by
Fascinating! In fact, what you just said corresponds to the number of permutations of a list of 3 numbers, or the number of ways to order a list of 3 numbers! That's a fascinating insight into the property of well-ordering and can be used to solve various difficult problems!


An alternate solution is to realise that all three planes pass through the line (t,t,t) for t varying. Therefore, we can see by an obvious symmetry that the space is split into 6 parts!
This post has been edited 1 time. Last edited by ohiorizzler1434, Yesterday at 12:01 AM
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oinava
506 posts
oinava
#5 h  Yesterday at 12:26 AM
Y by
Which obvious symmetry?

The x=0, y=0, z=0 planes all pass through the point (0,0,0), and cut the space into 8 regions.
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ohiorizzler1434
696 posts
ohiorizzler1434
#6 h  Yesterday at 1:25 AM
Y by
bro! that's because x=0, y=0, z=0 don't share a line lil bro! imagine if 3 planes shared a line. That's literally my point, the planes x=y, y=z, z=x share a line. Read my solution before you start saying your own contradictory and incorrect argument.
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