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

You are not logged in.

## #1 2012-12-18 09:30:58

Al-Allo
Full Member

Offline

### 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
Real Member

Offline

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

## #3 2012-12-18 09:55:28

Al-Allo
Full Member

Offline

### 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
Moderator

Offline

### 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
Full Member

Offline

### 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
Administrator

Offline

### 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.
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.

## #7 2012-12-18 14:08:50

Al-Allo
Full Member

Offline

### Re: probability

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

## Board footer

Powered by FluxBB