Is B correct? 10 points!

An airplane has 100 seats for passengers. Assume that the probability that a person holding a ticket appears for the flight is 0

zmey [24]

Answer:

96.33% probability that everyone who appears for the flight will get a seat

Step-by-step explanation:

I am going to use the binomial approximation to the normal 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:

$E(X) = np$

The standard deviation of the binomial distribution is:

$\sqrt{V(X)} = \sqrt{np(1-p)}$

Normal probability distribution

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

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

$Z = \frac{X - \mu}{\sigma}$

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 $\mu = E(X)$ , $\sigma = \sqrt{V(X)}$ .

In this problem, we have that:

$n = 105, p = 0.9$

So

$\mu = E(X) = np = 105*0.9 = 94.5$

$\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{105*0.9*0.1} = 3.07$

What is the probability that everyone who appears for the flight will get a seat

100 or less people appearing to the flight, which is the pvalue of Z when X = 100. So

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{100 - 94.5}{3.07}$

$Z = 1.79$

$Z = 1.79$ has a pvalue of 0.9633

96.33% probability that everyone who appears for the flight will get a seat

7 0

2 years ago

Mary makes trail mix with bulk nuts and dried fruit. She spends $4.50 on the dried fruit. Mixed nuts cost $2.50 per pound. She h

AnnyKZ [126]

Answer: 3 pounds

Step-by-step explanation: 12 - 4.50 = 7.50 7.50/2.50=3

4 0

3 years ago

2x+10=16 help please, i forgot how to work it out

JulsSmile [24]

Answer:

x=3

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

Rhea got a new e-scooter. She wanted to show it to her friend on the way to the library.Her friend ronan's house is due north of

Zepler [3.9K]

The distance between rhea and her friend's house could be 8 km and The distance of the library from the rocks house could be 15 km.

<h3>What is Pythagoras' Theorem?</h3>

If ABC is a triangle with AC as the hypotenuse and angle B with 90 degrees then we have:

|AC|^2 = |AB|^2 + |BC|^2

where |AB| = length of line segment AB. (AB and BC are rest of the two sides of that triangle ABC, AC being the hypotenuse).

rhea got a new e-scooter. She wanted to show it to her friend on the way to the library.

Her friend Ronan's house is due north of her house.

After showing him the new scooter she went to the library which is due west from rocks house.

while returning back she drove 17km diagonally to her house.

By Pythagoras' theorem

|AC|^2 = |AB|^2 + |BC|^2

Here we can assume that

AB = The distance between rhea and her friend's house.

BC = The distance of the library from rocks house.

The triplet of the 17 would be (8, 15, 17)

So, we can say that the AB could be 8 km and BC could be 15 km or vice versa.

Learn more about Pythagoras' theorem here:

brainly.com/question/12105522

#SPJ1

7 0

2 years ago

One survey showed that among 785 randomly selected subjects who completed four years of college, 18.3% smoke and a 98% confidenc

Valentin [98]

Answer

a. True

Step-by-step explanation:

Based on this survey we estimate that about $18.3\%$ of the college students smokes. And a $98\%$ confidence interval is $[15.1\% ; 21.6\%]$ . So we know that our estimative for the smoking rate is in the confidence interval with $98\%$ certainty. We also know the estimative for the smoking rate in the general population is $27\%$ . So we can write the two possible hypothesis:

$H_0 =$ Smoking rate is equal to $27\%$ .

$H_1 =$ Smoking rate is not equal to $27\%$ .

We will reject the null hypothesis $(H_0)$ if the estimate doesn't fall into the confidence interval for the college students smoking rate.

Since this condition holds we reject the null hypothesis. So with $98\%$ certainty we say that the smoking rate for the general population is different than the smoking rate for the college students.

6 0

2 years ago