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.

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.

Looking for summer camps in math and language arts? Be sure to check out the video-based summer camps offered at the Virtual Campus that are 2- to 4-weeks in duration. There are middle and high school competition math camps as well as Math Beasts camps that review key topics coupled with fun explorations covering areas such as graph theory (Math Beasts Camp 6), cryptography (Math Beasts Camp 7-8), and topology (Math Beasts Camp 8-9)!

Be sure to mark your calendars for the following events:
[list][*]April 3rd (Webinar), 4pm PT/7:00pm ET, Learning with AoPS: Perspectives from a Parent, Math Camp Instructor, and University Professor
[*]April 8th (Math Jam), 4:30pm PT/7:30pm ET, 2025 MATHCOUNTS State Discussion
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
Apr 2, 2025
0 replies
Website to learn math
hawa   47
N 2 hours ago by EthanNg6
Hi, I'm kinda curious what website do yall use to learn math, like i dont find any website thats fun to learn math
47 replies
hawa
Apr 9, 2025
EthanNg6
2 hours ago
Something Interesting
ilikemath247365   0
2 hours ago
I just realized: The 2013 National MathCounts Sprint #24 is the EXACT SAME as the 2001 National MathCounts Sprint #28.
0 replies
ilikemath247365
2 hours ago
0 replies
The daily problem!
Leeoz   121
N 3 hours ago by HacheB2031
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!
121 replies
Leeoz
Mar 21, 2025
HacheB2031
3 hours ago
0!??????
wizwilzo   58
N 4 hours ago by valisaxieamc
why is 0! "1" ??!
58 replies
wizwilzo
Jul 6, 2016
valisaxieamc
4 hours ago
No more topics!
Hello friends
bibidi_skibidi   9
N Apr 16, 2025 by giratina3
Now unfortunately I don't know the difficulty of the problems posted here but I'll try to replicate:

Bob has 20 apples and 19 oranges. How many ways can he split the fruits between 7 people if each person must have at least 1 apple and 2 oranges?

After looking at the other posters I realized just how bashy this is

Also I can only edit this message for now since new AoPS users can only send 6 messages every day
9 replies
bibidi_skibidi
Apr 15, 2025
giratina3
Apr 16, 2025
Hello friends
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bibidi_skibidi
5 posts
#1 • 2 Y
Y by aidan0626, GodGodGodGodGoose
Now unfortunately I don't know the difficulty of the problems posted here but I'll try to replicate:

Bob has 20 apples and 19 oranges. How many ways can he split the fruits between 7 people if each person must have at least 1 apple and 2 oranges?

After looking at the other posters I realized just how bashy this is

Also I can only edit this message for now since new AoPS users can only send 6 messages every day
This post has been edited 1 time. Last edited by bibidi_skibidi, Apr 15, 2025, 4:19 AM
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aidan0626
1863 posts
#2
Y by
Hi :)
This is standard stars and bars, there are $\binom{19}{6}$ ways to split the apples and $\binom{11}{6}$ ways to split the oranges, and you just multiply those two together to get the final answer.
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Soupboy0
342 posts
#3
Y by
bro i got sniped :rotfl:
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maxamc
564 posts
#4
Y by
aidan0626 wrote:
Hi :)
This is standard stars and bars, there are $\binom{19}{6}$ ways to split the apples and $\binom{11}{6}$ ways to split the oranges, and you just multiply those two together to get the final answer.

Wolfram Alpha gives 12534984 as our final answer (impossible to compute)
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fluffyyyyyyy
1 post
#5
Y by
hello sabko
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Leeoz
177 posts
#6
Y by
maxamc wrote:
aidan0626 wrote:
Hi :)
This is standard stars and bars, there are $\binom{19}{6}$ ways to split the apples and $\binom{11}{6}$ ways to split the oranges, and you just multiply those two together to get the final answer.

Wolfram Alpha gives 12534984 as our final answer (impossible to compute)

its not "impossible" :P
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Thayaden
1361 posts
#7
Y by
bibidi_skibidi wrote:
Now unfortunately I don't know the difficulty of the problems posted here but I'll try to replicate:

Bob has 20 apples and 19 oranges. How many ways can he split the fruits between 7 people if each person must have at least 1 apple and 2 oranges?

After looking at the other posters I realized just how bashy this is

Also I can only edit this message for now since new AoPS users can only send 6 messages every day

Start by giving away the required fruit this leaves 18 fruit for grabs namely 13 ap0pels and 5 oranges we set up stars and bars for extras and get (13+6)! but yet no oranges is diffrent from another orange and there are 5! ways to arage oranges and 13! ways to arange appels and 6! ways to arange bars so I think our answer is $\boxed{\frac{(18+6)!}{5!13!6!}}$ is what I got
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maxamc
564 posts
#8
Y by
Thayaden wrote:
bibidi_skibidi wrote:
Now unfortunately I don't know the difficulty of the problems posted here but I'll try to replicate:

Bob has 20 apples and 19 oranges. How many ways can he split the fruits between 7 people if each person must have at least 1 apple and 2 oranges?

After looking at the other posters I realized just how bashy this is

Also I can only edit this message for now since new AoPS users can only send 6 messages every day

Start by giving away the required fruit this leaves 18 fruit for grabs namely 13 ap0pels and 5 oranges we set up stars and bars for extras and get (13+6)! but yet no oranges is diffrent from another orange and there are 5! ways to arage oranges and 13! ways to arange appels and 6! ways to arange bars so I think our answer is $\boxed{\frac{(18+6)!}{5!13!6!}}$ is what I got

Your answer is 1153218528, not equal to my Wolfram Alpha answer described above, unfortunately wrong I think.
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BS2012
1024 posts
#9
Y by
its just Solution sketch which is the same as the 2nd post
This post has been edited 3 times. Last edited by BS2012, Apr 16, 2025, 12:52 AM
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giratina3
493 posts
#10
Y by
This is not bashy at all if you know Stars and Bars. I would recommend reading the later sections of Intro to Counting and Probability for more information.
This post has been edited 1 time. Last edited by giratina3, Apr 16, 2025, 2:57 AM
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