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#1 2012-12-20 04:16:57

jacks
Full Member

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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.

Thanks

#2 2012-12-20 04:53:23

bob bundy
Moderator

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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.

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

#3 2012-12-20 05:00:21

anonimnystefy
Real Member

Online

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