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AMC and other contests, summer programs, etc.
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Contests & Programs AMC and other contests, summer programs, etc.
AMC and other contests, summer programs, etc.
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k a My Retirement & New Leadership at AoPS
rrusczyk   1571
N Mar 26, 2025 by SmartGroot
I write today to announce my retirement as CEO from Art of Problem Solving. When I founded AoPS 22 years ago, I never imagined that we would reach so many students and families, or that we would find so many channels through which we discover, inspire, and train the great problem solvers of the next generation. I am very proud of all we have accomplished and I’m thankful for the many supporters who provided inspiration and encouragement along the way. I'm particularly grateful to all of the wonderful members of the AoPS Community!

I’m delighted to introduce our new leaders - Ben Kornell and Andrew Sutherland. Ben has extensive experience in education and edtech prior to joining AoPS as my successor as CEO, including starting like I did as a classroom teacher. He has a deep understanding of the value of our work because he’s an AoPS parent! Meanwhile, Andrew and I have common roots as founders of education companies; he launched Quizlet at age 15! His journey from founder to MIT to technology and product leader as our Chief Product Officer traces a pathway many of our students will follow in the years to come.

Thank you again for your support for Art of Problem Solving and we look forward to working with millions more wonderful problem solvers in the years to come.

And special thanks to all of the amazing AoPS team members who have helped build AoPS. We’ve come a long way from here:IMAGE
1571 replies
rrusczyk
Mar 24, 2025
SmartGroot
Mar 26, 2025
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]
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.

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0 replies
jlacosta
Mar 2, 2025
0 replies
Tennessee Math Tournament (TMT) Online 2025
TennesseeMathTournament   59
N 17 minutes ago by Cerberusman
Hello everyone! We are excited to announce a new competition, the Tennessee Math Tournament, created by the Tennessee Math Coalition! Anyone can participate in the virtual competition for free.

The testing window is from March 22nd to April 12th, 2025. Virtual competitors may participate in the competition at any time during that window.

The virtual competition consists of three rounds: Individual, Bullet, and Team. The Individual Round is 60 minutes long and consists of 30 questions (AMC 10 level). The Bullet Round is 20 minutes long and consists of 80 questions (Mathcounts Chapter level). The Team Round is 30 minutes long and consists of 16 questions (AMC 12 level). Virtual competitors may compete in teams of four, or choose to not participate in the team round.

To register and see more information, click here!

If you have any questions, please email connect@tnmathcoalition.org or reply to this thread!

Thank you to our lead sponsor, Jane Street!

IMAGE
59 replies
TennesseeMathTournament
Mar 9, 2025
Cerberusman
17 minutes ago
Mop Qual stuff
HopefullyMcNats2025   32
N 21 minutes ago by fake123
How good of an award/ achievement is making MOP, I adore comp math but am scared if I dedicate all my time to it I won’t get in a good college such as MIT or Harvard
32 replies
HopefullyMcNats2025
3 hours ago
fake123
21 minutes ago
USAJMO #5 - points on a circle
hrithikguy   207
N 32 minutes ago by LeYohan
Points $A,B,C,D,E$ lie on a circle $\omega$ and point $P$ lies outside the circle. The given points are such that (i) lines $PB$ and $PD$ are tangent to $\omega$, (ii) $P, A, C$ are collinear, and (iii) $DE \parallel AC$. Prove that $BE$ bisects $AC$.
207 replies
hrithikguy
Apr 28, 2011
LeYohan
32 minutes ago
9 Which math contest is your favorite?
mdk2013   15
N 36 minutes ago by mdk2013
mdk2013
Yesterday at 7:10 PM
mdk2013
36 minutes ago
No more topics!
AMC 10B #17
evt917   27
N Dec 16, 2024 by sadas123
Source: AMC 10B 2024 problem 17
In a race among 5 snails, there is at most one tie, but that tie can involve any number of snails. For example, the result of the race might be that Dazzler is first; Abby, Cyrus, and Elroy are tied for second, and Bruna is fifth. How many different results of the race are possible?

$
\textbf{(A) }180 \qquad
\textbf{(B) }361 \qquad
\textbf{(C) }420 \qquad
\textbf{(D) }431 \qquad
\textbf{(E) }720 \qquad
$
27 replies
evt917
Nov 13, 2024
sadas123
Dec 16, 2024
AMC 10B #17
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Source: AMC 10B 2024 problem 17
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evt917
2226 posts
#1
Y by
In a race among 5 snails, there is at most one tie, but that tie can involve any number of snails. For example, the result of the race might be that Dazzler is first; Abby, Cyrus, and Elroy are tied for second, and Bruna is fifth. How many different results of the race are possible?

$
\textbf{(A) }180 \qquad
\textbf{(B) }361 \qquad
\textbf{(C) }420 \qquad
\textbf{(D) }431 \qquad
\textbf{(E) }720 \qquad
$
This post has been edited 1 time. Last edited by Eternica, Mar 7, 2025, 5:14 PM
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gracemoon124
872 posts
#2
Y by
confirm (D)?
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Yihang2009
165 posts
#3
Y by
D is correct
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Mathiscool24
27 posts
#4
Y by
I got D: 431
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pingpongmerrily
3522 posts
#5
Y by
yeah super bashy confirm D

almost got this wrong :skull:
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andrewcheng
525 posts
#6
Y by
confirm D
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elizhang101412
1190 posts
#7
Y by
you could already narrow it down to b or d because there's the case that all snails tie
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aleyang
192 posts
#8
Y by
D, casework for how many snails tie
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mathboy282
2989 posts
#9 • 1 Y
Y by yishu15
0 tied: 5!
2 tied: (5c2), now you just arrange one "block" and 3 others so (5c2)4!
3 tied: 5c3 * 3!
4 tied: 5c4 *2!
5 tied: 1
120+240+60+10+1=431
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lucaswujc
293 posts
#10 • 1 Y
Y by yishu15
D its just casework
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zlrara01
335 posts
#11
Y by
this seemed really misplaced
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mathprodigy2011
244 posts
#12
Y by
I should've taken 10b bruh
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megarnie
5542 posts
#13 • 1 Y
Y by yishu15
Case 1: There exists a tie
The number of values for $m$ people in the tie is $\binom 5m \cdot (6-m )! = \frac{5! (6-m)}{m!} = (6-m) \cdot \prod_{i=m + 1}^5 i$.

Summing this from $m = 2$ to $m = 5$ gives $4 \cdot 60 + 3 \cdot 20 + 2 \cdot 5 + 1 = 311$.

Case 2: There is no tie
Then it's just $5! = 120$.

The answer is $311 + 120 = \boxed{\textbf{(D)}\ 431}$.
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VigneshS32
52 posts
#14 • 1 Y
Y by yishu15
I am glad that 430 wasn't an option. At first, I got 430 but then realized that I forgot the case where all of them tie. I fixed it and got 431(D)
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Soccerstar9
803 posts
#15
Y by
I missed the case where none of them were tied and I had 311. So I just let it blank :oops_sign:
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lpieleanu
2833 posts
#16
Y by
Solution
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Mr.Sharkman
490 posts
#17
Y by
The answer is $431.$

There are two cases.

Case 1: No ties. If this happens, we get $5! = 120.$

Case 2: One tie. Again, we split into more cases. If the tie contains $n$ people, then there are ${5 \choose n}$ ways to choose the people in the tie, and $(6-n)!$ ways to arrange the people (the tied people are consider “one person). So, adding over all $2 \le n \le 5,$ we get $311.$

Thus, we get $120+311=431,$ as desired.
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akliu
1742 posts
#18
Y by
Combo really fell off after P12; just casework here. I think there was a similar problem on the official AoPS AMC10 practice mock exam to this one.
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RabtejKalra
54 posts
#19
Y by
Bro, i left this blank cuz it felt too hard but i did it mentally on the car ride back :banging head
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stjwyl
1255 posts
#20
Y by
zlrara01 wrote:
this seemed really misplaced

yeah it was
Just casework bash
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zlrara01
335 posts
#21
Y by
It was a really nice bash too because it canceled out neatly
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aleyang
192 posts
#22
Y by
This was actually not that bad as I initially thought.
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Andyluo
885 posts
#23
Y by
https://www.mathcounts.org/sites/default/files/Solutions%202009-10%20Mini.pdf mathcounts mini #2, you just have to calculate if 2+ ties are possible and subtract, just thought it was interesting.
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Yiyj1
1188 posts
#25
Y by
SpeedCuber7 wrote:
please don't tell me i got this wrong

isnt it D
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SpeedCuber7
1763 posts
#26
Y by
Yiyj1 wrote:
SpeedCuber7 wrote:
please don't tell me i got this wrong

isnt it D

i dont know what i got

i am 1000% sure i put d
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Yiyj1
1188 posts
#27
Y by
SpeedCuber7 wrote:
Yiyj1 wrote:
SpeedCuber7 wrote:
please don't tell me i got this wrong

isnt it D

i dont know what i got

i am 1000% sure i put d

then you put d and you got it right :thumbsup:
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GP102
827 posts
#28
Y by
Easily one of the best questions on the test imo
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sadas123
1098 posts
#29
Y by
evt917 wrote:
In a race among 5 snails, there is at most one tie, but that tie can involve any number of snails. For example, the result of the race might be that Dazzler is first; Abby, Cyrus, and Elroy are tied for second, and Bruna is fifth. How many different results of the race are possible?


$
\textbf{(A) }180 \qquad
\textbf{(B) }361 \qquad
\textbf{(C) }420 \qquad
\textbf{(D) }431 \qquad
\textbf{(E) }720 \qquad
$

I remember on the actual test I took like 5 minutes just finding all of the casework :skull
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