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## #1 2012-12-18 09:30:58

Al-Allo
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### probability

I have just a little question about this : If I toss a coin 5 times, what is the probability of getting 4 tails and 1 head ? I think the answer is 5/32 ? Is this any good ? THanks

## #2 2012-12-18 09:49:55

anonimnystefy
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### Re: probability

5/32 is correct.

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

## #3 2012-12-18 09:55:28

Al-Allo
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### Re: probability

Omg im happy to know that because in my book it says its 4/32 ?!? And here is another one, what is the prob that it will land 3 times on head and 2 times on tails ? I got 9/32 but in my book it says 8/32 ?!? There is always 1 of difference, we could say it's an error ? Thanks !

## #4 2012-12-18 10:01:24

bob bundy
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### Re: probability

hi Al-Allo

Welcome to the forum.

Stay on-line.  I'm just working it out.

1 5 10 10 5 1

It should be 10/32

hhhtt, hhtht, hhtth, hthht, hthth, htthh, thhht, thhth, ththh, tthhh

Bob

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

## #5 2012-12-18 10:29:13

Al-Allo
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### Re: probability

oh yes you're right. i noticed i missed one, so thanks ! finaly, my book wasnt right ! thanks you two !

## #6 2012-12-18 11:16:56

bobbym

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### Re: probability

Hi Al-Allo;

Both of those are binomial distribution problems. What is the name of the book?

In mathematics, you don't understand things. You just get used to them.
90% of mathematicians do not understand 90% of currently published mathematics.
I am willing to wager that over 75% of the new words that appeared were nothing more than spelling errors that caught on.

## #7 2012-12-18 14:08:50

Al-Allo
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### Re: probability

It's not written in English ... ^^ Even, it's only exercises, nothing more lol