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
Doss [256]
2 years ago
11

According to the Knot, 22% of couples meet online. Assume the sampling distribution of p follows a normal distribution and answe

r the following questions.
a. Suppose a random sample of 150 couples is asked, "Did you meet online>" Describe the sampling distribution of p, the proportion of couples that met online.
b. What is the probability that in a random sample of 150 couples more than 25% met online?
c. What is the probability that in a random sample of 150 couples between 15% and 20% met online?
Mathematics
1 answer:
Ann [662]2 years ago
4 0

Using the <em>normal distribution and the central limit theorem</em>, we have that:

a) The sampling distribution is approximately normal, with mean 0.22 and standard error 0.0338.

b) There is a 0.1867 = 18.67% probability that in a random sample of 150 couples more than 25% met online.

c) There is a 0.2584 = 25.84% probability that in a random sample of 150 couples between 15% and 20% met online.

<h3>Normal Probability Distribution</h3>

In a normal distribution with mean \mu and standard deviation \sigma, the z-score of a measure X is given by:

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

  • It 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, which is the percentile of X.
  • By the Central Limit Theorem, for a proportion p in a sample of size n, the sampling distribution of sample proportion is approximately normal with mean \mu = p and standard deviation s = \sqrt{\frac{p(1 - p)}{n}}, as long as np \geq 10 and n(1 - p) \geq 10.

In this problem:

  • 22% of couples meet online, hence p = 0.22.
  • A sample of 150 couples is taken, hence n = 150.

Item a:

The mean and the standard error are given by:

\mu = p = 0.22

s = \sqrt{\frac{p(1 - p)}{n}} = \sqrt{\frac{0.22(0.78)}{150}} = 0.0338

The sampling distribution is approximately normal, with mean 0.22 and standard error 0.0338.

Item b:

The probability is <u>one subtracted by the p-value of Z when X = 0.25</u>, hence:

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

By the Central Limit Theorem:

Z = \frac{X - \mu}{s}

Z = \frac{0.25 - 0.22}{0.0338}

Z = 0.89

Z = 0.89 has a p-value of 0.8133.

1 - 0.8133 = 0.1867.

There is a 0.1867 = 18.67% probability that in a random sample of 150 couples more than 25% met online.

Item c:

The probability is the <u>p-value of Z when X = 0.2 subtracted by the p-value of Z when X = 0.15</u>, hence:

X = 0.2:

Z = \frac{X - \mu}{s}

Z = \frac{0.2 - 0.22}{0.0338}

Z = -0.59

Z = -0.59 has a p-value of 0.2776.

X = 0.15:

Z = \frac{X - \mu}{s}

Z = \frac{0.15 - 0.22}{0.0338}

Z = -2.07

Z = -2.07 has a p-value of 0.0192.

0.2776 - 0.0192 = 0.2584.

There is a 0.2584 = 25.84% probability that in a random sample of 150 couples between 15% and 20% met online.

To learn more about the <em>normal distribution and the central limit theorem</em>, you can check brainly.com/question/24663213

You might be interested in
Two integers, a and b, have a greatest common factor of 1. If a =12 and b is greater than 35 but no more than 40, what is the va
yarga [219]

Answer: 37

Step-by-step explanation:

a=12

35 < b < 40

\wedge\ means\ GCF\\a\ \wedge\ b= 1\\12\ \wedge\ 37= 1\\12\ \wedge\ 38= 2\\12\ \wedge\ 39= 3\\

7 0
2 years ago
I Need Help Like Now!!
kogti [31]

Answer:

\frac{136}{999}

Step-by-step explanation:

We require 2 equations with the repeating decimal after the decimal point in both equations.

The bar above 136 indicates that 136 is being repeated

let x = 0.136136...... → (1) Multiply both sides by 1000

1000x = 136.136.... → (2)

Subtract (1) from (2) to eliminate the decimal part

999x = 136 ( divide both sides by 999 )

x = \frac{136}{999}

5 0
3 years ago
The tire on a mountain bike measures 30 in. in diameter. A rider picks up a thorn in her tire as she passes through a patch of g
mixas84 [53]

Answer:

yrdjdhngessrhmsrymftfyhstdfkdtjyrarddtgjgbfffhr jganntfbeakye no tengo ru tkm re e

5 0
3 years ago
How to do proportional triangles
harina [27]

Answer: If the measures of the corresponding sides of two triangles are proportional then the triangles are similar. Likewise if the measures of two sides in one triangle are proportional to the corresponding sides in another triangle and the including angles are congruent then the triangles are similar.

Step-by-step explanation:

7 0
3 years ago
35% of f is 14. What is f? Enter your answer as a numeric expression.​
Nata [24]

Answer:

40

Step-by-step explanation:

14/35 = f/100

35f = 14 x 100

f = 14 x 100 /35

f = 40

7 0
2 years ago
Read 2 more answers
Other questions:
  • Similar figures always have .....?
    15·2 answers
  • Find the reciprocal of the number. Multiply to check your answer.
    7·2 answers
  • &lt;a and &lt;b are complementary angles. &lt;a measures 22<br>What is the measure of &lt;b?​
    9·1 answer
  • I really need help on this.
    8·2 answers
  • Need help with please
    11·1 answer
  • 36. Determine o valor de x em cada item:
    10·1 answer
  • To anyone who's in 8th grade, what did you learn in technology for 3rd quarter. like just give me the unit names or just what yo
    12·1 answer
  • Which equation could be true ?
    15·1 answer
  • If the product of the extremes is 8,then the geometric mean is
    5·1 answer
  • 2<br> _ y + 3 =15 What is y<br> 3
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!