How to identify if a probability question applies the concept of binomial distribution ?

Question

michele_laino · Answer

for example, if we have to study this event:
"I toss 25 coins, and I want to know what is the probability to get, for example, 10 heads"

michele_laino · Answer

in such example, I make 25 trials, and I want to get 10 successes.
the probability to get a head is 1/2, the probability to ge a tail is also 1/2, and the requested probability, is given by this quantity:
$$\Large  P = \left( {\begin{array}{*{20}{c}}
  {25} \ 
  {10} 
\end{array}} \right){\left( {\frac{1}{2}} \right)^{10}}{\left( {\frac{1}{2}} \right)^{\left( {25 - 10} \right)}}$$

mathmath333 · Answer

Is the following question using binomial distribution ?


The bag $A$ contains $3$ black balls and $5$ red balls while bag $B$ contains
$4$ black balls and $7$ red balls , If the $2$ balls extracted simultaneosuly
 from any of the two bags are found to be black, find the probability that they are found from bag $B$.

parthkohli · Answer

Probably conditional probability. Don't ask me though, I haven't studied it.

miracrown · Answer

Well, for your question, it is a binomial case when we are looking for the number of success in a sample. I mean, it could be (similar to the exercise) the number of red balls selected from a bag.

mathmath333 · Answer

ok thnks

miracrown · Answer

yw :)

mathmath333 · Answer

I will also request @Michele_Laino to comment .

sparrow2 · Answer

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