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k a April Highlights and 2025 AoPS Online Class Information
jlacosta   0
Yesterday at 3:18 PM
Spring is in full swing and summer is right around the corner, what are your plans? At AoPS Online our schedule has new classes starting now through July, so be sure to keep your skills sharp and be prepared for the Fall school year! Check out the schedule of upcoming classes below.

WOOT early bird pricing is in effect, don’t miss out! If you took MathWOOT Level 2 last year, no worries, it is all new problems this year! Our Worldwide Online Olympiad Training program is for high school level competitors. AoPS designed these courses to help our top students get the deep focus they need to succeed in their specific competition goals. Check out the details at this link for all our WOOT programs in math, computer science, chemistry, and physics.

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[list][*]April 3rd (Webinar), 4pm PT/7:00pm ET, Learning with AoPS: Perspectives from a Parent, Math Camp Instructor, and University Professor
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April 9th (Webinar), 4:00pm PT/7:00pm ET, Learn about Video-based Summer Camps at the Virtual Campus
[*]April 10th (Math Jam), 4:30pm PT/7:30pm ET, 2025 MathILy and MathILy-Er Math Jam: Multibackwards Numbers
[*]April 22nd (Webinar), 4:00pm PT/7:00pm ET, Competitive Programming at AoPS (USACO).[/list]
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0 replies
jlacosta
Yesterday at 3:18 PM
0 replies
prime factorization formula questions
Soupboy0   8
N an hour ago by martianrunner
If i have a number, say $N$ with prime factorization $p_1^{e_1}p_2^{e_2}...p_n^{e_n}$, and I want to find $3, 4, 5, ..., k$ numbers that multiply to $N$, does anybody know a formula for this?
8 replies
Soupboy0
2 hours ago
martianrunner
an hour ago
9 MATHCOUNTS STATE difficulty
Eddie_tiger   56
N 2 hours ago by giratina3
I personally thought the problems were much easier than last year, but I didn't really improve as much as I would of liked to improve.
56 replies
Eddie_tiger
Tuesday at 1:13 PM
giratina3
2 hours ago
2025 MATHCOUNTS State Hub
SirAppel   217
N 2 hours ago by morestuf
Previous Years' "Hubs": (2022) (2023) (2024)Please Read

Now that it's April and we're allowed to discuss, and no one else has made this yet ...
[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) *
[*] FL: 39 (42 41 40 39 38 37 37)
[*] IN: 39 (41 40 40 39 ?? 35)
[*] NC: 39 (42 42 41 39)
[*] IL: 38 (41 40 39 38 38 38)
[*] OR: 38 (44 41? 38 38)
[*] PA: 38 (41 40 40 38 38 37 36 36 34 34) *
[*] MD: 37 (43 39 39 37 37 37)
[*] CT: 36 (44 39? 38 36 34 34 34 34)
[*] 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)
[*] WI: 34 (40 37 37 34 35 30 28 29 29 29) *
[*] 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!
As per last year's guidelines, refrain from problem discussion until their official release on the MATHCOUNTS website.
217 replies
SirAppel
Tuesday at 12:22 PM
morestuf
2 hours ago
I cant find one problem
tanujkundu   9
N 3 hours ago by vsarg
Does anybody know which problem is about when a number is a meteor and when a number is a shooting star?
9 replies
tanujkundu
Sep 17, 2024
vsarg
3 hours ago
No more topics!
Something Horrible-a Challenge
Xueshuxue   23
N Mar 31, 2025 by Demetri
Hello, I was wondering if it's possible to make 8 with the numbers 5, 3, 5, and 7 under the following rules:
-You can only use 5 twice, 3 once, and 7 once.
-You must use all the numbers.
You can stack numbers to form larger numbers (example: I could take 3 and 5 and turn it into 35 or 53, or use 7, 3, and 5 to make 375.)
-You are allowed to use parentheses.
(Also, I already found out that no 3 digital numbers will work for the solution.)
23 replies
Xueshuxue
Mar 28, 2025
Demetri
Mar 31, 2025
Something Horrible-a Challenge
G H J
G H BBookmark kLocked kLocked NReply
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Xueshuxue
45 posts
#1
Y by
Hello, I was wondering if it's possible to make 8 with the numbers 5, 3, 5, and 7 under the following rules:
-You can only use 5 twice, 3 once, and 7 once.
-You must use all the numbers.
You can stack numbers to form larger numbers (example: I could take 3 and 5 and turn it into 35 or 53, or use 7, 3, and 5 to make 375.)
-You are allowed to use parentheses.
(Also, I already found out that no 3 digital numbers will work for the solution.)
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Inaaya
216 posts
#2
Y by
(5x3)-7 !!!
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sanaops9
815 posts
#3
Y by
you need to use both fives rbo

you didn't mention what functions to use so $\lfloor{\dfrac{55+3}{7}\rfloor}$
This post has been edited 1 time. Last edited by sanaops9, Mar 28, 2025, 7:28 PM
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derekwang2048
1204 posts
#4
Y by
if you're allowed to use more than just the basic operations, this is simple
This post has been edited 2 times. Last edited by derekwang2048, Mar 28, 2025, 7:29 PM
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sanaops9
815 posts
#5
Y by
@above, you can use \lfloor and \rfloor for left floor and right floor, respectively.

EDIT: ig u figured it out
This post has been edited 2 times. Last edited by sanaops9, Mar 28, 2025, 7:31 PM
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vincentwant
1282 posts
#6 • 1 Y
Y by ARWonder
Click to reveal hidden text
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Solocraftsolo
2458 posts
#7
Y by
the answer is obviously

\[|P\left(\left\lfloor \sqrt{\sqrt{\left\lceil \sqrt{\left\lfloor \sqrt{\left\lceil \sqrt{\sqrt{\left\lfloor \sqrt{\sqrt{\left\lceil \sqrt{\sqrt{\sqrt{5537}}}\right\rceil !!}}\right\rfloor !}}\right\rceil !}\right\rfloor !}\right\rceil !}}\right\rfloor\right)|\]

where the P function is the power set and the | | means cardinality
This post has been edited 1 time. Last edited by Solocraftsolo, Mar 28, 2025, 8:51 PM
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Leeoz
165 posts
#8 • 2 Y
Y by Exponent11, TTNT
chat gpt cooked
chat gpt wrote:
To make 8 using only the numbers **3**, **5**, **5**, and **7**, one possible solution is:

\[
(5 + 5) - (7 - 3) = 8
\]
Explanation:
- First, add the two 5s: \(5 + 5 = 10\).
- Then, subtract the difference between 7 and 3: \(7 - 3 = 4\).
- Finally, subtract 4 from 10: \(10 - 4 = 8\).

This gives you 8!
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ChickensEatGrass
42 posts
#9
Y by
Leeoz wrote:
chat gpt cooked
chat gpt wrote:
To make 8 using only the numbers **3**, **5**, **5**, and **7**, one possible solution is:

\[
(5 + 5) - (7 - 3) = 8
\]
Explanation:
- First, add the two 5s: \(5 + 5 = 10\).
- Then, subtract the difference between 7 and 3: \(7 - 3 = 4\).
- Finally, subtract 4 from 10: \(10 - 4 = 8\).

This gives you 8!

what the heck
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huajun78
48 posts
#11
Y by
Leeoz wrote:
chat gpt cooked
chat gpt wrote:
To make 8 using only the numbers **3**, **5**, **5**, and **7**, one possible solution is:

\[
(5 + 5) - (7 - 3) = 8
\]
Explanation:
- First, add the two 5s: \(5 + 5 = 10\).
- Then, subtract the difference between 7 and 3: \(7 - 3 = 4\).
- Finally, subtract 4 from 10: \(10 - 4 = 8\).

This gives you 8!

$6=8$, proof by ChatGPT
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SirAppel
861 posts
#12
Y by
$(5+3)^{\lfloor \frac{7}{5} \rfloor}$
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cheltstudent
548 posts
#13
Y by
$lcm(7,5) - 3^{3}=8$
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Soupboy0
265 posts
#14 • 1 Y
Y by PuppyPenguinDolphin
$\frac{5!}{3!}-5-7$
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Owen314159
9 posts
#15
Y by
Soupboy0 wrote:
$\frac{5!}{3!}-5-7$

I think this is the most normal sol
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RandomMathGuy500
54 posts
#16
Y by
chat gpt wrote:
You can make 8 using the numbers 5, 5, 3, and 7 with the following equation:
$(7+3)-(5+5)=8$
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Total_Awesomeness
240 posts
#17
Y by
derekwang2048 wrote:
if you're allowed to use more than just the basic operations, this is simple

ur not allowed to use 8
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happymoose666
294 posts
#18
Y by
he is not using 8, it's an equal sign
This post has been edited 1 time. Last edited by happymoose666, Mar 29, 2025, 10:37 PM
Reason: yes
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Total_Awesomeness
240 posts
#19
Y by
no at the end
he says that it equals the digit 8, which is not allowed
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sanaops9
815 posts
#20
Y by
Owen314159 wrote:
Soupboy0 wrote:
$\frac{5!}{3!}-5-7$

I think this is the most normal sol
vincentwant wrote:
Click to reveal hidden text

No vincent's was prolly the best and intended sol
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pieMax2713
4168 posts
#21
Y by
$|\{5, 5, 7\}|^3$ where | | denotes cardinality
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K1mchi_
6 posts
#22 • 1 Y
Y by ChickensEatGrass
(7!/(5!+3!))/5
I just used lots of factorial
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WiseHawkCuteFriendly
565 posts
#23
Y by
chat gpt wrote:
$\frac{7+5}{3}+5=8$,
reasoning: $\frac{12}{3}+5=8$
$4+5=8$
This post has been edited 2 times. Last edited by WiseHawkCuteFriendly, Mar 31, 2025, 1:46 AM
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happymoose666
294 posts
#24
Y by
Total_Awesomeness wrote:
no at the end
he says that it equals the digit 8, which is not allowed

But he meant $\frac{55+\lfloor{\sqrt3}\rfloor}{7}$ is equal to 8, so he solved the problem, he is not using eight
This post has been edited 2 times. Last edited by happymoose666, Mar 31, 2025, 1:21 PM
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Demetri
1184 posts
#25
Y by
Soupboy0 wrote:
$\frac{5!}{3!}-5-7$

I think this is the most normal sol
This doesn't use factorials
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