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k a May Highlights and 2025 AoPS Online Class Information
jlacosta   0
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]
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0 replies
jlacosta
May 1, 2025
0 replies
J
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Wrong Answer on a Street Math Challenge
miguel00   2
N an hour ago by miguel00
Hello AoPS Community,

I was just watching this video link (those of you that are Korean, you should watch it!) but I came across a pretty hard vector geometry problem (keep in mind contestants have to solve this problem in 5 minutes). No one got this problem (no surprise there) but I am posting because I actually think the answer he gave is wrong.

So the problem goes like this: Referencing the diagram attached, there are three externally tangent circles $C_1, C_2, C_3$ on a plane with centers $O_1, O_2, O_3$, respectively. $H$ is feet of the perpendicular from $O_1$ to $O_2O_3$ and $A$ and $B$ are intersections of line $O_1H$ with circle $C_1$. Points $P$ and $Q$ can move around the circle $C_2$ and $C_3$, respectively. Find the maximum possible value of $|\overrightarrow{AQ}+\overrightarrow{PB}|$.


I got my answer but the video said their 1st answer but they later corrected it on the comments to their 2nd answer. I'll let you guys attempt the problem and will give my solution shortly after. Thanks in advance!

-miguel00
2 replies
+1 w
miguel00
an hour ago
miguel00
an hour ago
J
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Introducing a math summer program for middle school students
harry133   0
2 hours ago
Introducing IITSP, an online math summer program designed for middle school students over summer.

The program is designed by Professor Shubhrangshu Dasgupta from the Department of Physics at the Indian Institute of Technology Ropar (IIT Ropar).

Please check out the webpage if you are interested in.

https://www.imc-impea.org/IMC/bbs/content.php?co_id=iitsp
0 replies
harry133
2 hours ago
0 replies
J
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2 headed arrows usage
mathprodigy2011   1
N 4 hours ago by alcumusftwgrind
Source: 2003 USAMO 4
I can't upload the file but I was working with someone on 2003 USAMO p4. When we saw "if and only if" I thought it meant we have to prove it both directions. However, when we looked at Evan Chen's solution after writing it out; Evan Chen used double headed arrows and left it at that. My question is, how did he use them and how do I know when I can or can not use them?
1 reply
mathprodigy2011
4 hours ago
alcumusftwgrind
4 hours ago
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4th grader qual JMO
HCM2001   42
N Yesterday at 6:58 PM by BS2012
i mean.. whattttt??? just found out about this.. is he on aops? (i'm sure he is) where are you orz lol..
https://www.mathschool.com/blog/results/celebrating-success-douglas-zhang-is-rsm-s-youngest-usajmo-qualifier
42 replies
HCM2001
May 22, 2025
BS2012
Yesterday at 6:58 PM
J
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Correlation between USAMO and CMO qualification
rantaccountcs   7
N Apr 7, 2025 by elasticwealth
What is the correlation between cmo qualification and usamo qualification? What proportion of Canadian usamo qualifiers are cmo qualifiers and what proportion of cmo qualifiers are usamo qualifiers?
7 replies
rantaccountcs
Nov 2, 2023
elasticwealth
Apr 7, 2025
J
Correlation between USAMO and CMO qualification
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rantaccountcs
156 posts
rantaccountcs
#1 h  Nov 2, 2023, 7:56 PM
Y by
What is the correlation between cmo qualification and usamo qualification? What proportion of Canadian usamo qualifiers are cmo qualifiers and what proportion of cmo qualifiers are usamo qualifiers?
Z K Y
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David_Kim_0202
384 posts
David_Kim_0202
#2 h  Nov 3, 2023, 3:47 AM
Y by
can usa people take canadian math competitions?
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mrtheory
7 posts
mrtheory
#3 h  Mar 30, 2025, 6:03 PM
Y by
David_Kim_0202 wrote:
can usa people take canadian math competitions?

yes
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BS2012
1057 posts
BS2012
#4 h  Mar 30, 2025, 6:14 PM
Y by
mrtheory wrote:
David_Kim_0202 wrote:
can usa people take canadian math competitions?

yes

Really?
https://cms.math.ca/competitions/cmo/#CMOeligibility wrote:
In order to be an official participant, all competitors:

must be a Canadian Citizen or Permanent Resident of Canada (but not necessarily residing in Canada currently),

must not have formally enrolled at a university or any other equivalent post-secondary institution and must not yet have graduated from high school (or equivalent),

must be currently attending school full-time since the start of the current school year,

must be less than 20 years old as of June 30 of the year of the Competition.

Additionally, the CJMO requires that competitors must be in grade ten or earlier.
(https://cms.math.ca/competitions/cmo/#CMOeligibility)
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mrtheory
7 posts
mrtheory
#5 h  Apr 7, 2025, 3:12 AM
Y by
@BS2012 Oh my fault I might have mixed it up Canadians can participate in USA math competitions but like CMS stated USA students shouldn't be able to
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babyzombievillager
410 posts
babyzombievillager
#6 h  Apr 7, 2025, 3:32 AM
Y by
BS2012 wrote:
mrtheory wrote:
David_Kim_0202 wrote:
can usa people take canadian math competitions?

yes

Really?
https://cms.math.ca/competitions/cmo/#CMOeligibility wrote:
In order to be an official participant, all competitors:

must be a Canadian Citizen or Permanent Resident of Canada (but not necessarily residing in Canada currently),

must not have formally enrolled at a university or any other equivalent post-secondary institution and must not yet have graduated from high school (or equivalent),

must be currently attending school full-time since the start of the current school year,

must be less than 20 years old as of June 30 of the year of the Competition.

Additionally, the CJMO requires that competitors must be in grade ten or earlier.
(https://cms.math.ca/competitions/cmo/#CMOeligibility)

does anyone remember the jcoons post about Canadians competing in American olympiads lol
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BS2012
1057 posts
BS2012
#7 h  Apr 7, 2025, 11:37 AM
Y by
babyzombievillager wrote:
...

does anyone remember the jcoons post about Canadians competing in American olympiads lol
bruh they can
americans cant participate in canadian olympiads but canadians can participate in american ones
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elasticwealth
342 posts
elasticwealth
#8 h  Apr 7, 2025, 11:42 AM
Y by
reasonable crash out imo
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