Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

## #26 2013-01-09 05:58:00

anonimnystefy
Real Member

Offline

### Re: probability

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
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #27 2013-01-09 06:00:14

bobbym

Online

### 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.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #28 2013-05-22 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 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 2013-05-22 09:17:38

bobbym

Online

### 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.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #30 2013-05-22 14:36:25

anonimnystefy
Real Member

Offline

### 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
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #31 2013-05-22 14:56:09

Agnishom
Real Member

Offline

### Re: probability

#### bobbym wrote:

Yes, I see that.

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'
'Who are you to judge everything?' -Alokananda

## #32 2013-05-22 18:27:01

bobbym

Online

### Re: probability

For post #1.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.