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VOLUNTEERING OPPORTUNITY OPEN TO HIGH/MIDDLE SCHOOLERS
im_space_cadet   11
N 40 minutes ago by im_space_cadet
Hi everyone!
Do you specialize in contest math? Do you have a passion for teaching? Do you want to help leverage those college apps? Well, I have something for all of you.

I am im_space_cadet, and during the fall of last year, I opened my non-profit DeltaMathPrep which teaches students preparing for contest math the problem-solving skills they need in order to succeed at these competitions. Currently, we are very much understaffed and would greatly appreciate the help of more tutors on our platform.

Each week on Saturday and Wednesday, we meet once for each competition: Wednesday for AMC 8 and Saturday for AMC 10 and we go over a past year paper for the entire class. On both of these days, we meet at 9PM EST in the night.

This is a great opportunity for anyone who is looking to have a solid activity to add to their college resumes that requires low effort from tutors and is very flexible with regards to time.

This is the link to our non-profit for anyone who would like to view our initiative:
https://www.deltamathprep.org/

If you are interested in this opportunity, please send me a DM on AoPS or respond to this post expressing your interest. I look forward to having you all on the team!

Thanks,
im_space_cadet
11 replies
im_space_cadet
Today at 2:26 PM
im_space_cadet
40 minutes ago
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random problem i just thought about one day
ceilingfan404   0
an hour ago
i don't even know if this is solvable
Prove that there are finite/infinite powers of 2 where all the digits are also powers of 2. (For example, $4$ and $128$ are numbers that work, but $64$ and $1024$ don't work.)
0 replies
ceilingfan404
an hour ago
0 replies
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9 Did you get into Illinois middle school math Olympiad?
Gavin_Deng   2
N an hour ago by Pi_isCool31415
I am simply curious of who got in.
2 replies
Gavin_Deng
Yesterday at 9:05 PM
Pi_isCool31415
an hour ago
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Weird Similarity
mithu542   3
N 4 hours ago by zhoujef000
Is it just me or are the 2023 national sprint #21 and 2025 state target #4 strangely similar?
[quote=2023 Natioinal Sprint #21] A right triangle with integer side lengths has perimeter $N$ feet and area $N$ ft^2. What is the arithmetic mean of all possible values of $N$?[/quote]
[quote=2025 State Target #4]Suppose a right triangle has an area of 20 cm^2 and a perimeter of 40 cm. What is
the length of the hypotenuse, in centimeters?[/quote]
3 replies
mithu542
Apr 18, 2025
zhoujef000
4 hours ago
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2025 MATHCOUNTS State Hub
SirAppel   582
N 4 hours ago by Shan3t
Previous Years' "Hubs": (2022) (2023) (2024)Please Read

Now that it's April and we're allowed to discuss ...
[list=disc]
[*] CA: 43 (45 44 43 43 43 42 42 41 41 41)
[*] NJ: 43 (45 44 44 43 39 42 40 40 39 38) *
[*] NY: 42 (43 42 42 42 41 40)
[*] TX: 42 (43 43 43 42 42 40 40 38 38 38)
[*] MA: 41 (45 43 42 41)
[*] WA: 41 (41 45 42 41 41 41 41 41 41 40) *
[*]VA: 40 (41 40 40 40)
[*] FL: 39 (42 41 40 39 38 37 37)
[*] IN: 39 (41 40 40 39 36 35 35 35 34 34)
[*] NC: 39 (42 42 41 39)
[*] IL: 38 (41 40 39 38 38 38)
[*] OR: 38 (44 39 38 38)
[*] PA: 38 (41 40 40 38 38 37 36 36 34 34) *
[*] MD: 37 (43 39 39 37 37 37)
[*] AZ: 36 (40? 39? 39 36)
[*] CT: 36 (44 38 38 36 35 35 34 34 34 33 33)
[*] MI: 36 (39 41 41 36 37 37 36 36 36 36) *
[*] MN: 36 (40 36 36 36 35 35 35 34)
[*] CO: 35 (41 37 37 35 35 35 ?? 31 31 30) *
[*] GA: 35 (38 37 36 35 34 34 34 34 34 33)
[*] OH: 35 (41 37 36 35)
[*] AR: 34 (46 45 35 34 33 31 31 31 29 29)
[*] NV: 34 (41 38 ?? 34)
[*] TN: 34 (38 ?? ?? 34)
[*] WI: 34 (40 37 37 34 35 30 28 29 29 29) *
[*] HI: 32 (35 34 32 32)
[*] NH: 31 (42 35 33 31 30)
[*] DE: 30 (34 33 32 30 30 29 28 27 26? 24)
[*] SC: 30 (33 33 31 30)
[*] IA: 29 (33 30 31 29 29 29 29 29 29 29 29 29) *
[*] NE: 28 (34 30 28 28 27 27 26 26 25 25)
[*] SD: 22 (30 29 24 22 22 22 21 21 20 20)
[/list]
Cutoffs Unknown

* means that CDR is official in that state.

Notes

For those asking about the removal of the tiers, I'd like to quote Jason himself:
[quote=peace09]
learn from my mistakes
[/quote]

Help contribute by sharing your state's cutoffs!
582 replies
SirAppel
Apr 1, 2025
Shan3t
4 hours ago
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9 What is the most important topic in maths competition?
AVIKRIS   34
N 5 hours ago by b2025tyx
I think arithmetic is the most the most important topic in math competitions.
34 replies
AVIKRIS
Yesterday at 5:29 PM
b2025tyx
5 hours ago
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mathcounts state discussion
Soupboy0   65
N Today at 7:00 AM by ERMSCoach
les goo its finally april
65 replies
Soupboy0
Apr 1, 2025
ERMSCoach
Today at 7:00 AM
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2025 MathCounts State Competition Sprint #30
ilikemath247365   6
N Today at 6:30 AM by ERMSCoach
If $x$ and $y$ are real numbers such that $(4 - x)(4 + y) = 2$ and $(4 + x)(4 - y) = 3$, what is the value of $(x^{2} - 1)(y^{2} - 1)$? Express your answer as a common fraction.
6 replies
ilikemath247365
Apr 5, 2025
ERMSCoach
Today at 6:30 AM
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2025 MATHCOUNTS State Target #8
ERMSCoach   0
Today at 6:25 AM
The solution is wrong.

2/27 probability is for three flips, so the 'correct' answer from this solution should have been 27/2 * 3= 81/2 flips.

The correct answer for THT is 31/2.

The correct solution:

Let $E_H$ be the expected number of flips to get HTT after getting an H.
Then $E_H$ = (case TT) 1/3 * 1/3 * 2 + (case TH) 1/3 * 2/3 * ($E_H$+2) + (case H) 2/3 * ($E_H$+1)
$E_H$= 12
E = (case H) 2/3* (1+$E_H$) + (case T) 1/3*(1+E)
E=27/2

The only argument that can be made for this solution is the answer of 1/P is correct for sequences of H followed by Ts.
0 replies
ERMSCoach
Today at 6:25 AM
0 replies
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The daily problem!
Leeoz   117
N Today at 6:07 AM by aidan0626
Every day, I will try to post a new problem for you all to solve! If you want to post a daily problem, you can! :)

Please hide solutions and answers, hints are fine though! :)

Problems usually get harder throughout the week, so Sunday is the easiest and Saturday is the hardest!

Past Problems!
117 replies
1 viewing
Leeoz
Mar 21, 2025
aidan0626
Today at 6:07 AM
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A Problem on a Rectangle
buratinogigle   0
Apr 16, 2025
Source: VN Math Olympiad For High School Students P11 - 2025 - Bonus, MM Problem 2197
Let $ABCD$ be a rectangle and $P$ any point. Let $X, Y, Z, W, S, T$ be the foots of the perpendiculars from $P$ to the lines $AB, BC, CD, DA, BD, AC$, respectively. Let the perpendicular bisectors of $XY$ and $WZ$ intersect at $Q$, and those of $YZ$ and $XW$ intersect at $R$. Prove that the lines $QR$ and $ST$ are parallel.

MM Problem
0 replies
buratinogigle
Apr 16, 2025
0 replies
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A Problem on a Rectangle
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Source: VN Math Olympiad For High School Students P11 - 2025 - Bonus, MM Problem 2197
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buratinogigle
2344 posts
buratinogigle
#1 h  Apr 16, 2025, 1:42 AM
Y by
Let $ABCD$ be a rectangle and $P$ any point. Let $X, Y, Z, W, S, T$ be the foots of the perpendiculars from $P$ to the lines $AB, BC, CD, DA, BD, AC$, respectively. Let the perpendicular bisectors of $XY$ and $WZ$ intersect at $Q$, and those of $YZ$ and $XW$ intersect at $R$. Prove that the lines $QR$ and $ST$ are parallel.

MM Problem
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