You have a really annoying stapler that seems to randomly jam. On any given attempt to staple, it seems to independently jam 10.9% of the time. a) Out of 260 papers stapled, what is the probability that your stapler will jam less than 23 times? Round your answer to 4 decimals.

Respuesta :

Answer:

0.1230 = 12.30% probability that your stapler will jam less than 23 times

Step-by-step explanation:

I am going to use the normal approximation to the binomial distribution to solve this question.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

[tex]E(X) = np[/tex]

The standard deviation of the binomial distribution is:

[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]

Normal probability distribution

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

When we are approximating a binomial distribution to a normal one, we have that [tex]\mu = E(X)[/tex], [tex]\sigma = \sqrt{V(X)}[/tex].

In this problem, we have that:

[tex]p = 0.109, n = 260[/tex]

So

[tex]\mu = E(X) = np = 260*0.109 = 28.34[/tex]

[tex]\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{260*0.109*0.891} = 5.025[/tex]

Out of 260 papers stapled, what is the probability that your stapler will jam less than 23 times?

This is P(X < 23).

Using continuity correction, this is P(X < 23-0.5) = P(X < 22.5), which is the pvalue of Z when X = 22.5. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{22.5 - 28.34}{5.025}[/tex]

[tex]Z = -1.16[/tex]

[tex]Z = -1.16[/tex] has a pvalue of 0.1230

0.1230 = 12.30% probability that your stapler will jam less than 23 times

The probability that your stapler will jam less than 23 times is 12.30 %

Probability :

It is given that, On any given attempt to staple, it seems to independently jam 10.9% of the time.

Probability of success[tex]p=0.109,n=260[/tex]

Mean [tex]\mu=np=260*0.109=28.34[/tex]

standard deviation [tex]\sigma=\sqrt{np(1-p)} =5.025[/tex]

We have to find  the probability that your stapler will jam less than 23 times.

It means that, [tex]P(X < 23)[/tex], this is the p value of z when [tex]X=23-0.5=22.5[/tex]

To find z- value,

               [tex]z=\frac{X-\mu}{\sigma} \\\\z=\frac{22.5-28.34}{5.025} =-1.16[/tex]

From z value table, for [tex]z=-1.16[/tex], p- value is [tex]0.1230[/tex].

Thus, the probability that your stapler will jam less than 23 times is [tex]12.30\%[/tex]

Learn more about the standard deviation here:

https://brainly.com/question/12402189