Stay ahead of learning milestones! Enroll in a class over the summer!

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k a April Highlights and 2025 AoPS Online Class Information
jlacosta   0
Apr 2, 2025
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.

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[*]April 22nd (Webinar), 4:00pm PT/7:00pm ET, Competitive Programming at AoPS (USACO).[/list]
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0 replies
jlacosta
Apr 2, 2025
0 replies
EaZ_Shadow
Apr 6, 2025
Craftybutterfly
Today at 5:56 AM
Math and AI 4 Girls
mkwhe   18
N Today at 5:43 AM by EvaLin
Hey everyone!

The 2025 MA4G competition is now open!

Apply Here: https://xmathandai4girls.submittable.com/submit


Visit https://www.mathandai4girls.org/ to get started!

Feel free to PM or email mathandai4girls@yahoo.com if you have any questions!
18 replies
mkwhe
Apr 5, 2025
EvaLin
Today at 5:43 AM
The daily problem!
Leeoz   106
N Today at 4:44 AM by Leeoz
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!
106 replies
Leeoz
Mar 21, 2025
Leeoz
Today at 4:44 AM
2025 MATHCOUNTS State Hub
SirAppel   551
N Today at 3:24 AM by DhruvJha
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 40? 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!
551 replies
SirAppel
Apr 1, 2025
DhruvJha
Today at 3:24 AM
No more topics!
Something Horrible-a Challenge
Xueshuxue   24
N Apr 7, 2025 by Solocraftsolo
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.)
24 replies
Xueshuxue
Mar 28, 2025
Solocraftsolo
Apr 7, 2025
Something Horrible-a Challenge
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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
257 posts
#2
Y by
(5x3)-7 !!!
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sanaops9
822 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
1219 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
822 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
1293 posts
#6 • 1 Y
Y by ARWonder
Click to reveal hidden text
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Solocraftsolo
2492 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
174 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
44 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
61 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
872 posts
#12
Y by
$(5+3)^{\lfloor \frac{7}{5} \rfloor}$
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cheltstudent
567 posts
#13
Y by
$lcm(7,5) - 3^{3}=8$
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Soupboy0
322 posts
#14 • 1 Y
Y by PuppyPenguinDolphin
$\frac{5!}{3!}-5-7$
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Owen314159
12 posts
#15
Y by
Soupboy0 wrote:
$\frac{5!}{3!}-5-7$

I think this is the most normal sol
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RandomMathGuy500
57 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
288 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
301 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
288 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
822 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
4176 posts
#21
Y by
$|\{5, 5, 7\}|^3$ where | | denotes cardinality
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K1mchi_
23 posts
#22 • 1 Y
Y by ChickensEatGrass
(7!/(5!+3!))/5
I just used lots of factorial
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WiseHawkCuteFriendly
580 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
301 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
1272 posts
#25
Y by
Soupboy0 wrote:
$\frac{5!}{3!}-5-7$

I think this is the most normal sol
This doesn't use factorials
Click to reveal hidden text
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Solocraftsolo
2492 posts
#26 • 1 Y
Y by Exponent11
huajun78 wrote:

$6=8$, proof by ChatGPT

proof by exhaustion
proof by contradiction
proof by chatGPT
This post has been edited 1 time. Last edited by Solocraftsolo, Apr 7, 2025, 4:10 PM
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