100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Math 225N Week 5 Assignment (2020) - Central Limit Theorem for Proportions. Graded A $13.49   Add to cart

Exam (elaborations)

Math 225N Week 5 Assignment (2020) - Central Limit Theorem for Proportions. Graded A

 3 views  0 purchase
  • Course
  • Institution

1. A dental student is conducting a study on the number of people who visit their dentist regularly. Of the 520 people surveyed, 312 indicated that they had visited their dentist within the past year. Find the population proportion, as well as the mean and standard deviation of the sampling distrib...

[Show more]

Preview 3 out of 22  pages

  • May 20, 2022
  • 22
  • 2021/2022
  • Exam (elaborations)
  • Questions & answers
avatar-seller
Central Limit Theorem for Proportions
Week 5 Assignment:
1. A dental student is conducting a study on the number of people who visit
their dentist regularly. Of the 520 people surveyed, 312 indicated that they
had visited their dentist within the past year.
Find the population proportion, as well as the mean and standard deviation
of the sampling distribution for samples of size n=60.
Correct answers:
 10 point 6 0 0 $0.600$0.600
 20 point 6 0 0 $0.600$0.600
 30 point 0 6 3 $0.063$0.063


The population proportion is p=312520≈0.600. This is also the mean of
the sampling distribution:

μp^=p=0.600

For samples of size n=60, the standard deviation of the sampling
distribution is

σpˆ=p(1−p)n−−−−−−−√=0.600(1−0.600)60−−−−−−−−−
−−−−−√≈0.063
2. From recent census data, it is discovered that the proportion of the adults in the United
States who are first generation Americans is 14%. For a random sample of size 500,
what is standard deviation for the sampling distribution of the sample proportions,
rounded to three decimal places?

---Given the population proportion p=14%=0.14 and a sample size of
n=500, the standard deviation of the sampling distribution of sample
proportions is

σpˆ=p(1−p)n−−−−−−−√=0.14(1−0.14)500−−−−−−−−−−
−−√≈0.016

,3. From recent survey data, a car buying business finds that 12.5% of the proportion of
adults in a city would be likely to use their services. For a random sample of 115 people,
what is standard deviation for the sampling distribution of the sample proportions,
rounded to three decimal places?

Given the population proportion p=12.5%=0.125 and a sample size of
n=115, the standard deviation of the sampling distribution of sample
proportions is
σpˆ=p(1−p)n−−−−−−−√=0.125(1−0.125)115−−−−−−−−−
−−−−−√≈0.031
4. Question
From recent survey data, its known that the proportion of adults in the United
States who are smokers is 18%. For a random sample of size 150, what is
standard deviation for the sampling distribution of the sample proportions,
rounded to three decimal places?

Given the population proportion p=18%=0.18 and a sample size of n=150,
the standard deviation of the sampling distribution of sample proportions is
σpˆ=p(1−p)n−−−−−−−√=0.18(1−0.18)150−−−−−−−−−−
−−√≈0.031
5. A small community college has a population of 986 students, 252 of
whom them are considered non-traditional students.

Find the population proportion, as well as the mean and standard deviation
of the sampling distribution for samples of size n=40.

Round all answers to 3 decimal places.

The population proportion is p=252986≈0.256. This is also the mean of
the sampling distribution:

μp^=p=0.256

For samples of size n=40, the standard deviation of the sampling
distribution is

, σpˆ=p(1−p)n−−−−−−−√=0.256(1−0.256)40−−−−−−−−−
−−−−−√≈0.069
6. A marketing team is targeting people who might buy a hybrid car. In their
city, with a population of 30,000 people, 3,170 people either drive a
hybrid car or have indicated on a recent survey that they would be interested
in driving one. Find the population proportion, as well as the mean and standard
deviation of the sampling distribution for samples of size n=121.

he population proportion is p=3,17030,000≈0.106. This is also the
mean of the sampling distribution:

μp^=p=0.106

For samples of size n=121, the standard deviation of the sampling
distribution is

σpˆ=p(1−p)n−−−−−−−√=0.106(1−0.106)121−−−−−−−−−
−−−−−√≈0.028
7. A brokerage company is analyzing its retirement accounts for its clients nearing
retirement. From recent survey data, the proportion of adults in the United States who say
they are financially ready for retirement is 31%. For a random sample of size 85, what is
standard deviation for the sampling distribution of the sample proportions, rounded to
three decimal places?

Given the population proportion p=31%=0.31 and a sample size of n=85,
the standard deviation of the sampling distribution of sample proportions is

σpˆ=p(1−p)n−−−−−−−√=0.31(1−0.31)85−−−−−−−−−−−
−√≈0.050
8. Question
Given the plot of normal distributions A and B below, which of the following
statements is true? Select all correct answers.

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller ELITESOLUTIONS. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $13.49. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

67232 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
$13.49
  • (0)
  Add to cart