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k a April Highlights and 2025 AoPS Online Class Information
jlacosta   0
Apr 2, 2025
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0 replies
jlacosta
Apr 2, 2025
0 replies
J
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100th post! (actually 105)
K1mchi_   3
N 2 minutes ago by evt917
here’s a math problem!
if the aops forum has 50 users and the users post once a minute, then how many posts will be made in a week? note that Fred and ted are twins and Elizabeth only visits the forum on weekends. assume that the users do not post during the 5 hour school day and 8 hours of sleep, but also that they have no life and only grind AOPS. it is not a leap year

anyway

this is my 105th post and I feel like I’ve grown a lot
not rlly lol
i have remained the same perfect person hahaha

Click to reveal hidden text
3 replies
K1mchi_
2 hours ago
evt917
2 minutes ago
J
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2025 MATHCOUNTS State Target #8
ERMSCoach   1
N 18 minutes ago by pieMax2713
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.
1 reply
ERMSCoach
Apr 20, 2025
pieMax2713
18 minutes ago
J
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random problem i just thought about one day
ceilingfan404   21
N 20 minutes ago by K3mchi_
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.)
21 replies
ceilingfan404
Apr 20, 2025
K3mchi_
20 minutes ago
J
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Geometry
BQK   11
N 21 minutes ago by K3mchi_
Help me, Why geometry is so difficult to learn
11 replies
BQK
Yesterday at 2:58 PM
K3mchi_
21 minutes ago
J
No more topics!
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cutoffs for RSM IMC
bubby617   27
N Apr 14, 2025 by RabtejKalra
what are the percentile cutoffs for the RSM IMC? i got in with an 82nd percentile so im curious on the requirements for advancement in R1/prizes in R2
27 replies
bubby617
Apr 12, 2025
RabtejKalra
Apr 14, 2025
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cutoffs for RSM IMC
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Reveal topic tags
RSM IMC
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bubby617
5 posts
bubby617
#1 h  Apr 12, 2025, 10:18 PM • 1 Y
Y by RainbowJessa
what are the percentile cutoffs for the RSM IMC? i got in with an 82nd percentile so im curious on the requirements for advancement in R1/prizes in R2
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jb2015007
1919 posts
jb2015007
#2 h  Apr 12, 2025, 10:27 PM • 1 Y
Y by RainbowJessa
im taking r2 in 2hours
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ZMB038
104 posts
ZMB038
#3 h  Apr 12, 2025, 10:36 PM • 1 Y
Y by RainbowJessa
What is RSM IMC?
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RabtejKalra
65 posts
RabtejKalra
#4 h  Apr 12, 2025, 11:39 PM • 1 Y
Y by RainbowJessa
When are we allowed to discuss the problems?
This post has been edited 1 time. Last edited by RabtejKalra, Apr 12, 2025, 11:40 PM
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ethan2011
299 posts
ethan2011
#5 h  Apr 12, 2025, 11:57 PM • 1 Y
Y by RainbowJessa
ZMB038 wrote:
What is RSM IMC?

I think Russian School Math International Math Competition? Someone correct me if I'm wrong.
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Jaxman8
115 posts
Jaxman8
#7 h  Apr 13, 2025, 2:58 AM • 1 Y
Y by RainbowJessa
Correct.
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apex304
524 posts
apex304
#8 h  Apr 13, 2025, 3:28 AM • 2 Y
Y by RainbowJessa, EthanNg6
bubby617 wrote:
what are the percentile cutoffs for the RSM IMC? i got in with an 82nd percentile so im curious on the requirements for advancement in R1/prizes in R2

where do you see the percentiles? I got a 14 on r1 but idk what percentile that is...
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RabtejKalra
65 posts
RabtejKalra
#9 h  Apr 13, 2025, 3:39 AM • 1 Y
Y by RainbowJessa
I'm pretty sure you have to buy the performance report
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RabtejKalra
65 posts
RabtejKalra
#10 h  Apr 13, 2025, 3:39 AM • 1 Y
Y by RainbowJessa
How do you think you did on the second round
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jb2015007
1919 posts
jb2015007
#11 h  Apr 13, 2025, 3:50 AM • 1 Y
Y by RainbowJessa
10/12 prolly bc of sillies
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ZMB038
104 posts
ZMB038
#12 h  Apr 13, 2025, 2:21 PM • 1 Y
Y by RainbowJessa
ethan2011 wrote:
ZMB038 wrote:
What is RSM IMC?

I think Russian School Math International Math Competition? Someone correct me if I'm wrong.

Thanks Ethan2011, maybe I'll try it next year.
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littlebigbull
566 posts
littlebigbull
#13 h  Apr 14, 2025, 12:21 AM • 1 Y
Y by RainbowJessa
bro i messed up i thought it is today but at 11 i checks and it was yesterday so i took it and i was so tired sob!
think i got 10/12 tho
8 and 11 messed me up
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jb2015007
1919 posts
jb2015007
#14 h  Apr 14, 2025, 12:52 AM • 1 Y
Y by RainbowJessa
11 and 12 messed me up bro i spent 45 mins on 1 question js to cheese it
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sadas123
1232 posts
sadas123
#15 h  Apr 14, 2025, 12:53 AM • 1 Y
Y by RainbowJessa
is this a proof compeititon? or is it mcq or is it fr?
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jb2015007
1919 posts
jb2015007
#16 h  Apr 14, 2025, 1:06 AM • 1 Y
Y by RainbowJessa
Its short answer
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sadas123
1232 posts
sadas123
#17 h  Apr 14, 2025, 1:18 AM • 1 Y
Y by RainbowJessa
jb2015007 wrote:
Its short answer

ohh thanks!
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MathCosine
150 posts
MathCosine
#18 h  Apr 14, 2025, 1:29 AM • 1 Y
Y by RainbowJessa
jb2015007 wrote:
11 and 12 messed me up bro i spent 45 mins on 1 question js to cheese it

was it that hard?

on a side note
This post has been edited 1 time. Last edited by MathCosine, Apr 14, 2025, 2:11 AM
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Schintalpati
615 posts
Schintalpati
#19 h  Apr 14, 2025, 1:37 AM • 1 Y
Y by RainbowJessa
I didn't do #12 cuz I had to go somewhere lol, so I submitted the test right after finishing 1-11, 11 is fine ig
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jb2015007
1919 posts
jb2015007
#20 h  Apr 14, 2025, 1:42 AM • 1 Y
Y by RainbowJessa
bruh schinilpati finally didnt perfect in something lol
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jb2015007
1919 posts
jb2015007
#21 h  Apr 14, 2025, 1:43 AM • 1 Y
Y by RainbowJessa
MathCosine wrote:
jb2015007 wrote:
11 and 12 messed me up bro i spent 45 mins on 1 question js to cheese it

was it that hard?

on a side note

no it was rlly ez i was prolly js delusional it was super ez and after that long i barely solved it with time to spare
This post has been edited 1 time. Last edited by jb2015007, Apr 14, 2025, 1:43 AM
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Schintalpati
615 posts
Schintalpati
#22 h  Apr 14, 2025, 1:43 AM • 1 Y
Y by RainbowJessa
jb2015007 wrote:
bruh schinilpati finally didnt perfect in something lol

not true bruh I rarely perfect :skull:
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jb2015007
1919 posts
jb2015007
#23 h  Apr 14, 2025, 1:44 AM • 1 Y
Y by RainbowJessa
11 and 12 were doable for me in like 5 mins but i spent like 3/5 of the time on that one question bro :wallbash_red:
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apex304
524 posts
apex304
#24 h  Apr 14, 2025, 1:58 AM • 1 Y
Y by RainbowJessa
bro wasn't 12 on 8th grade like 504?
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MathCosine
150 posts
MathCosine
#25 h  Apr 14, 2025, 2:11 AM
Y by
apex304 wrote:
bro wasn't 12 on 8th grade like [REDACTED NUMERAL]?

yeah yeah 7-8 test i got that too
phew my perfect is safe for now
This post has been edited 1 time. Last edited by MathCosine, Apr 14, 2025, 2:43 AM
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jb2015007
1919 posts
jb2015007
#26 h  Apr 14, 2025, 2:42 AM
Y by
lol i guessed 1434
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jb2015007
1919 posts
jb2015007
#27 h  Apr 14, 2025, 2:43 AM
Y by
idk if were allowed to discuss tho so lets js refrain from talking about it to be safe
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apex304
524 posts
apex304
#28 h  Apr 14, 2025, 2:56 AM
Y by
MathCosine wrote:
apex304 wrote:
bro wasn't 12 on 8th grade like [REDACTED NUMERAL]?

yeah yeah 7-8 test i got that too
phew my perfect is safe for now

same lol :)
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RabtejKalra
65 posts
RabtejKalra
#29 h  Apr 14, 2025, 10:41 PM
Y by
For 12 on 5th grade, i got 1280, dunno if that's what you guys got
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