Question

five dice are rolled.find the probability that three dice show the composite number

Answer 1

do u know what is composite no's ?

Answer 2

no

Answer 3

help

Answer 4

composite no are those no. with are not prime..

Answer 5

4,6,8,10,12,9,etc

Answer 6

2^6/6^6

Answer 7

yep right.. and i am not sure about the answer

Answer 8

64/7776

Answer 9

nope in the numerator something wrong

Answer 10

It's a binomial distribution. \(p=1/3\). since 2 of 6 sides are composite. Also \(1-p=2/3\),\(k=3\), and \(n=5\)
\[
\Pr(k=3) = \binom{5}{2}(1/3)^3(1-1/3)^{5-3}
\]
That gives me \(40/243\approx 16.5\%\)

http://www.wolframalpha.com/input/?i=%285+choose+2%29%281%2F3%29%5E3%281-1%2F3%29%5E%7B5-3%7D

Answer 11

The binomial distribution is as follows. You have some event which succeeds with probability \(p\). In this case the event is a dice roll. You need repeat the trial \(n\) times and \(X\) is the random variable representing the number of successes. \[
\Pr(X=k)=\binom{n}{k}p^k(1-p)^{n-k}
\]

Answer 12

In this case we wanted \(X=k=3\) successes out of the \(n=5\) trials. The success probability was \(p=2/6=1/3\) because there are two composite numbers \(4\) and \(6\) out of all number on a die: \(1,2,3,4,5,6\).

Answer 13

how 2 of 6 are composite.plse explain @wio

Answer 14

\(4=2\times 2\) and \(6=3\times 2\)

Answer 15

\(2\), \(3\), and \(5\) are prime. \(1\) is not composite.

Answer 16

k understood wio.i have a confusion always btw a permutations ,probability etc can u explain .how to know permutations and probability. and binomial distribution

Answer 17

I already explain binomial distribution.

Answer 18

k .then permutation and probability

Answer 19

I'm tired.

Answer 20

its k .tell me the website to learn these topics clearly

Answer 21

thank u very much.

Answer 22

do u know cat exam

Answer 23

http://www.mathsisfun.com/combinatorics/combinations-permutations.html