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A little help here? (II-B Combinatorics HW)

 
 
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A little help here? (II-B Combinatorics HW)
by David Tang - Friday, 3 January 2020, 12:03 PM
 

Excuse me, I'm David Tang from MC2B, and I don't even know how to do 28) on Counting Methods, pt. 2.


I would like you to do a favor and give me a hint.


Thanks.


Sincerely, David Tang 2020

 
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Re: A little help here? (II-B Combinatorics HW)
by Areteem Professor - Friday, 3 January 2020, 5:11 PM
 

You might be tempted to use stars and bars, however, this time the balls are not identical so stars and bars would not help.

Instead start by placing $10$ balls into the first box (how many ways can you pick the $10$ balls that will go in this box?), and then place each of the remaining $20$ balls into one of the $5$ remaining boxes (you can do this one ball at a time).

Let us know if you need additional hints for this problem. Happy New Year!