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#1 2012-12-20 04:16:57

Full Member


dice probability using Tree Diagram

A fair dice is rolled . the probability that the first time one occur at even no. of trails

Can any one explain me using Tree Diagram.


#2 2012-12-20 04:53:23

bob bundy


Re: dice probability using Tree Diagram

hi jacks,

You may throw a one straight away, or on throw 2, or on throw 3, or on throw 4, or ...........

See diagram.

P(one at first throw) = 1/6
P(one at second throw) = 5/6 times 1/6 = 5/36
P(one at third throw) = 5/6 x 5/6 x 1/6 = 25/216

etc etc.

As this goes on for ever you need to know how to do the sum to infinity of a geometric progression.  Post again if you want help with that.


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#3 2012-12-20 05:00:21

Real Member


Re: dice probability using Tree Diagram

Hi jacks

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

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