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#1 2012-12-04 22:15:31
- Jhua4
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Help! Discrete mathematics
You have 25 cards, 15 distinguishable envelopes (i.e. envelopes are labeled 1,2,3...,15). You may put any non-negative number of cards into an envelope. In how many ways can you put the 25 cards if
a) the cards are distinguishable (e.g., if each has different message on it)
b) cards are identical
c) cards are identical and no card can be left empty
I can't figure out the answers for this problem. Help is much appreciated!
Last edited by Jhua4 (2012-12-04 22:17:54)
#3 2012-12-04 22:42:04
- bobbym
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Re: Help! Discrete mathematics
Thats for n1, n2, n3 number of cards in each each envelope..
My formula has some envelopes empty so it is not correct.
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#5 2012-12-04 22:55:52
- bobbym
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Re: Help! Discrete mathematics
Hi;
Non negative means 0,1,2,3,4,5 so some boxes can be empty.
a)
ways.
b)
ways.
c)
ways.
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#7 2012-12-04 23:21:21
- bobbym
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Re: Help! Discrete mathematics
Hi;
Please hold on I am getting the answers to the problems. I am putting them in post #5. When I have all the computation done, I will explain the methods.
c) cards are identical and no card can be left empty
This question is incorrect.
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#9 2012-12-04 23:35:32
- bobbym
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Re: Help! Discrete mathematics
Hi;
Post #5 contains all the answers you require.
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.
#11 2012-12-04 23:51:16
- bobbym
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Re: Help! Discrete mathematics
Hi;
Basically, you are just plugging into formulas, check post #5 again.
In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.