1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Sergio [31]
3 years ago
8

The rates of on-time flights for commercial jets are continuously tracked by the U.S. Department of Transportation. Recently, So

uthwest Air had the best rate with 80 % of its flights arriving on time. A test is conducted by randomly selecting 15 Southwest flights and observing whether they arrive on time. (a) Find the probability that at least 2 flights arrive late.
Mathematics
1 answer:
densk [106]3 years ago
6 0

Answer:

83.29% probability that at least 2 flights arrive late.

Step-by-step explanation:

For each flight, there are only two possible outcomes. Either it arrives late, or it does not arrive late. The probability of a flight arriving late is independent of other flights. So we use the binomial probability distribution to solve this question.

Binomial probability distribution

The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

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

In which C_{n,x} is the number of different combinations of x objects from a set of n elements, given by the following formula.

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

And p is the probability of X happening.

80 % of its flights arriving on time.

So 100 - 80 = 20% arrive late, which means that p = 0.2

15 Southwest flights

This means that n = 15

Find the probability that at least 2 flights arrive late.

Either less than two arrive late, or at least 2 do. The sum of the probabilities of these outcomes is 1. So

P(X < 2) + P(X \geq 2) = 1

We want P(X \geq 2)

Then

P(X \geq 2) = 1 - P(X < 2)

In which

P(X < 2) = P(X = 0) + P(X = 1)

So

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

P(X = 0) = C_{15,0}.(0.2)^{0}.(0.8)^{15} = 0.0352

P(X = 1) = C_{15,1}.(0.2)^{1}.(0.8)^{14} = 0.1319

P(X < 2) = P(X = 0) + P(X = 1) = 0.0352 + 0.1319 = 0.1671

Then

P(X \geq 2) = 1 - P(X < 2) = 1 - 0.1671 = 0.8329

83.29% probability that at least 2 flights arrive late.

You might be interested in
8. What do you know about triangles PDX and triangle CRX? Justify your answer.
s2008m [1.1K]
If segment PD is parallel to segment CR then triangle PDX is similar to triangle CRX, due to angle PXD and angle CXR being congruent by the vertical angle theorem, and angle PDX and angle CRX being congruent by the alternate interior angle theorem, these 2 triangles are similar by the A.A similarity postulate.
5 0
1 year ago
Read 2 more answers
Anyone......plzzz......​
Vikentia [17]
Could u send me a bigger picture so I can help!
4 0
3 years ago
Exercise 1.6 introduces a study on the relationship between socio-economic class and unethical behavior. As part of this study 1
lbvjy [14]

Answer:

(A) Population: UCB undergraduates

Sample: The selected 129 UCB undergraduates

(B) Yes, they can be generalized to the population

No, the findings of this <em>single</em> study cannot be used to establish causal relationships between socio-economic classes and unethical behaviors.

Step-by-step explanation:

STUDY: Relationship between socio-economic class and unethical behavior.

The bases for determining social class here are:  money, education, and respected job.

RESULT: Those who identified as upper class took more candy than others.

(A) Identify the population of interest and the sample, in this study.

The population of interest in this study is UCB undergraduates.

The sample in this study is the 129 UCB undergraduates who were selected and who agreed to take part in the experiment. They were the participants who were divided into the two social classes before the experiment was conducted.

(B) The results of the study can be generalized to the population of UCB undergraduates since it's likely that the results would be same in another group of 129 UCB undergraduates.

The findings or results of the study cannot be used to establish causal relationships unless the study is conducted in more universities and majority of the results are same with this.

6 0
3 years ago
65 inches is how many feet? (Round to nearest hundredth) *
nalin [4]

Answer:

5.42 feet

Step-by-step explanation:

12 inches=1 foot

65/12=5.41667

5.41667=5.42 feet

7 0
2 years ago
Read 2 more answers
You intended to ride all of the rides exactly one time each at the waterpark. Which would be least expensive: pay separately or
djverab [1.8K]
I believe the answer is but a all day pass
6 0
2 years ago
Read 2 more answers
Other questions:
  • What is the Pythagorean theorem of 9in and 12in triangle
    10·2 answers
  • Function f is an exponential function. x −1 1 3 5 7 f(x) 14 4 64 1024 16,234 By what factor does the output value increase as ea
    6·1 answer
  • What are the factors of the polynomial below?
    6·1 answer
  • 4.5(x–2)= 13 ????????????
    8·2 answers
  • NEED HELP!! 25 POINTSS!!!
    15·1 answer
  • Which of the system has only one solution?
    5·1 answer
  • Arrange the following numbers in ascending order:<br> 34 566, 356 333, 3657, 305 760
    11·2 answers
  • The circle has a circumference of 9.42 units. What is the area of the square? Use 3.14 for π. Explain how you found the answer.
    9·1 answer
  • nicole is making carrot bread. she needs 5 cups of carrots for every 2 cups of sugar. what is the ratio of cups of sugar to cups
    6·1 answer
  • Please i will give brainliest if right
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!