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#26 2013-01-09 05:58:00

anonimnystefy
Real Member

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Re: probability

We could continue in your thread in Computer Math about diophantine equations.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

#27 2013-01-09 06:00:14

bobbym
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Re: probability

That is not what I meant. GF's are rather obscure and not taught. He/she will probably expect a solution in terms of ncr's.


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.

#28 Yesterday 08:47:13

Batman
Guest

Re: probability

What you could do is say the kids got a, b, c, d, d (the twins each got the same) and then seek quadruples satisfiing a+b+c+2d=13 than try each value of d.
d=0: 13 candies 3 kids place dividers in ccccccccccccc (c for CANDY!) and see the number of ways we can put the 3 dividers (3 kids left) so 15 choose 2 = 105
d=1: same, 13 choose 2 = 78   
d=2: same logic, 11 choose 2 = 55
d=3: ditto I stop saying same tongue 9 choose 2 = 36
d=4: 7 choose 2 = 21
d=5: 5 choose 2 = 10
d=6: 3 choose 2 = 3
105+78+55+36+21+10+3=308
I got 308

#29 Yesterday 09:17:38

bobbym
Administrator

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Re: probability

Hi;

Welcome to the forum, 308 is the correct answer.


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.

#30 Yesterday 14:36:25

anonimnystefy
Real Member

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Re: probability

That looks like something that would please the OP.

By the way, I just though of a twist to the puzzle to make it just a bit harder.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

#31 Yesterday 14:56:09

Agnishom
Super Member

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Re: probability

bobbym wrote:

Yes, I see that.

How about the recurrence:



with a(0)=1,a(1)=3

This is for what?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'The whole person changes, why can't a habit?' -65

#32 Yesterday 18:27:01

bobbym
Administrator

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Re: probability

For post #1.


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.

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