For each question, there are only two possible outcomes, either she gets it right or she does not get it right. The probability of getting a question right is independent of any other question, hence the <em>binomial distribution</em> is used to solve this question.

<h3>What is the binomial distribution formula?</h3>

The formula is:

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$C_{n,x} = \frac{n!}{x!(n-x)!}$

The parameters are:

x is the number of successes.

n is the number of trials.

p is the probability of a success on a single trial.

In this problem:

There are 5 questions, hence n = 5.

For each question, she guesses one out of 4 options, hence p = 1/4 = 0.25.

The probability that she guesses at least one right is:

$P(X \geq 1) = 1 - P(X = 0)$

In which:

$P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}$

$P(X = 0) = C_{4,0}.(0.25)^{0}.(0.75)^{4} = 0.3164$

Hence:

$P(X \geq 1) = 1 - P(X = 0) = 1 - 0.3164 = 0.6836$

0.6836 = 68.36% probability that she guesses at least one right.

You can learn more about the binomial distribution at brainly.com/question/24863377

8 0

2 years ago

If someone ran over a dog could they die if they neck breaks

bixtya [17]

Explanation:

it depends on which part he ran over. dogs are said to be of high strength, any action of inadequate pressure or power would not necessarily be fatal. if the right amount of energy is used at the right spot, for example an artery running through the neck ( like the carotid artery) or something. but since the dog apparently vanished, we could make out that it is not exactly dead

7 0

3 years ago