2.

The table below contains the amount that a sample of nine customers spent for lunch​ ($) at a​ fast-food restaurant. Complete parts a and b below.

4.26 5.23 5.67 6.28 7.44 7.51 8.25 8.69 9.61

Construct a 99% confidence interval estimate for the population mean amount spent for lunch at a fast-food restaurant, assuming normal distribution.

The % confidence interval estimate is from $____________to $___________

3.

he table below contains a certain social media​ company's penetration values​ (the percentage of a​ country's population that use this social​ media) for 14 countries. Complete parts a through c below.

a. Construct a 95​% confidence interval estimate for the population mean social media penetration.The 95​% confidence interval estimate is from

4. In a survey of 2,442 website​ users, 1,871 cited​ "seeing photos or​ videos" as a major reason why they use a​ website, while 1,233 cited​ "keeping up with news and current​ events" as a major reason why they use a website. Complete parts​ (a) through​ (c) below.

Construct a​ 95% confidence interval estimate for the population proportion of website users who cited​ "seeing photos or​ videos" as a major reason why they use a website.

5. If the manager of a bottled water distributor wants to​estimate, with 95% confidence, the mean amount of water in a​1-gallon bottle to within ±0.003 gallons and also assumes that the standard deviation is 0.05 ​gallons, what sample size is​needed?

n=?

6.In a study of 402 nonprofits​ nationwide, 80 indicated that turnover has been the biggest employment challenge at their organization. Complete parts​ (a) through​ (c).

Construct a 95% confidence interval for the population proportion of nonprofits that indicate turnover as the biggest employment challenge at their organization.

1. Consider the data shown in the following table.
   1. Identify any modifications that would result in a more effective table.
   2. Comment the characteristics of participants.

Baseline Characteristics of Participants in Randomized Trial

A person is interested in constructing a portfolio. Two stocks are being considered. Let x = percent return for an investment in stock 1, and y = percent return for an investment in stock 2. The expected return and variance for stock 1 are E(x) = 8.55% and  Var(x) = 25. The expected return and variance for stock 2 are E(y) = 3.40% and Var(y) = 1. The covariance between the returns is σ_xy = −3.

(a)

What is the standard deviation (as a percent) for an investment in stock 1?

%

What is the standard deviation (as a percent) for an investment in stock 2?

%

Using the standard deviation as a measure of risk, which of these stocks is the riskier investment?

An investment in stock 1  ---Select--- would would not  be risky compared with an investment in stock 2.

(b)

What is the expected return and standard deviation, in dollars, for a person who invests $600 in stock 1?

expected return$ standard deviation$

(c)

What is the expected percent return and standard deviation (as a percent) for a person who constructs a portfolio by investing 50% in each stock? (Round your answer for standard deviation to four decimal places.)

expected return %standard deviation %

(d)

What is the expected percent return and standard deviation for a person who constructs a portfolio by investing 70% in stock 1 and 30% in stock 2? (Round your answer for standard deviation to four decimal places.)

expected return %standard deviation %

(e)

Compute the correlation coefficient for x and y.

Comment on the relationship between the returns for the two stocks.

There is  ---strong positive or a strong negative or not a --- relationship between the variables.

A cheese processing company wants to estimate the mean cholesterol content of all one-ounce servings of cheese. The estimate must be within 0.3 milligram of the population mean. Assume the population standard deviation is 2.9 milligrams. Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Determine the minimum sample size required to construct a 98% confidence interval for the population mean. Which level of confidence requires a larger sample size? 90% 98%

Please Use your keyboard (Don't use handwriting) Thank you..

Courses Name: Introduction to Biostatistics PHC 121

Please answer the following questions:

***Please i need 500 words ..

I need new and unique answers, please. (Use your own words, don't copy and paste)

Q1. Discuss the tools to measure central tendency?

Q2.

a) Discuss parametric and nonparametric test used for    hypothesis testing.

    b) In a cross sectional study on coronary heart disease (CHD), the smoking and CHD status is summarized below. Use appropriate statistical test to conclude smoking plays any role in CHD.

***Please i need 500 words ..

I need new and unique answers, please. (Use your own words, don't copy and paste)

In an annual poll about consumption habits, telephone interviews were conducted for a random sample of 1,016 adults aged 18 and over. One of the questions was, "How many cups of coffee, if any, do you drink on an average day?" The following table shows the results obtained.

Define a random variable x = number of cups of coffee consumed on an average day. Let

x = 4

represent four or more cups.

(a)

Develop a probability distribution for x. (Round your answers to three decimal places.)

(b)

Compute the expected value of x. (Round your answer to three decimal places.)

E(x) =

(c)

Compute the variance of x. (Round your answer to three decimal places.)

Var(x) =

(d)

Suppose we are only interested in adults who drink at least one cup of coffee on an average day. For this group, let y = the number of cups of coffee consumed on an average day. Compute the expected value of y. (Round your answer to three decimal places.)

E(y) =

Compare the expected value of y to the expected value of x.

When we only take into account adults that drink at least one cup of coffee per day, the expected value is  ---Select--- equal to higher than lower than the expected value of x.

When playing roulette at a​ casino, a gambler is trying to decide whether to bet ​$15 on the number 28 or to bet ​$15 that the outcome is any one of the three possibilities 00 comma 0 comma or 1. The gambler knows that the expected value of the ​$15 bet for a single number is negative $ 1.58. For the ​$15 bet that the outcome is 00 comma 0 comma or 1​, there is a probability of StartFraction 3 Over 38 EndFraction of making a net profit of ​$45 and a StartFraction 35 Over 38 EndFraction probability of losing ​$15.

a. Find the expected value for the ​$15 bet that the outcome is 00 comma 0 comma or 1.

b. Which bet is​ better: a ​$15 bet on the number 28 or a ​$15 bet that the outcome is any one of the numbers 00 comma 0 comma or 1​? ​Why?

1. An expensive watch is powered by a​ 3-volt lithium battery expected to last

five years. Suppose the life of the battery has a standard deviation of 0.3 year and is normally distributed.

a. Determine the probability that the​ watch's battery will last longer than 5.4 years.

b. Calculate the probability that the​ watch's battery will last more than 4.45 years.

c. Compute the​ length-of-life value for which 15​% of the​ watch's batteries last longer.

2. Doggie Nuggets Inc.​ (DNI) sells large bags of dog food to warehouse clubs. DNI uses an automatic filling process to fill the bags. Weights of the filled bags are approximately normally distributed with a mean of 56 kilograms and a standard deviation of 0.86 kilograms. Complete parts a through d below.

a. What is the probability that a filled bag will weigh less than 55.2 kilograms?

On October 17, 2007, the classified ads on the web site of The Seattle Times listed the following 13 used Toyota Prius automobiles for sale; the data set below shows the year, color, mileage (in miles) and asking price (in U.S. dollars) for each car:

year     color      mileage     price
2006     green        17043     25995
2007     gray         12628     24980
2005     maroon       24039     24885
2005     silver       48226     23995
2006     black        10522     22995
2004     silver       66345     21995
2007     white         5611     21995
2005     gold         24479     21595
2004     white        14618     20995
2005     silver       53699     20980
2004     silver       47649     17995
2003     white        39600     17500
2005     black       103126     16995

We wish to investigate a possible association between the mileageof each Prius and its price. You should construct a scatterplot of this data.

assume that a linear model is appropriate, regardless of your answer to the previous question.

1. Find the equation of the regression line for this data that predicts price based upon mileage:

2. Use the model to predict the asking price of a Toyota Prius with 450,000 miles, or explain why such a prediction is not appropriate:

3. Use the model to predict the asking price of a Toyota Prius with 45,000 miles, or explain why such a prediction is not appropriate:

4. Compute the residual for the green Prius:

A bearing used in an automotive application is required to have a nominal inside diameter of 1.5 inches. A random sample of 25 bearings is selected and the average inside diameter of these bearings is 1.4975 inches. Bearing diameter is known to be normally distributed with standard deviation 1inch. (a) Test the hypotheses 1.5 versus 1.5 using 0.01 The true mean hole diameter Entry field with correct answer significantly different from 1.5 in. at alpha equals 0.01. (b) What is the P-value for the test in part (a)? P-value = Entry field with incorrect answer now contains modified data Round your answer to two decimal places (e.g. 98.76). (c) Compute the power of the test if the true mean diameter is 1.495 inches. Power of the test = Entry field with incorrect answer now contains modified data Round your answer to two decimal places (e.g. 98.76). (d) What sample size would be required to detect a true mean diameter as low as 1.495 inches if we wanted the power of the test to be at least 0.89? Entry field with incorrect answer now contains modified data bearings

A global research study found that the majority of today's working women would prefer a better work-life balance to an increased salary. One of the most important contributors to work-life balance identified by the survey was "flexibility," with 41% of women saying that having a flexible work schedule is either very important or extremely important to their career success.

d. If a sample of 400 is​ taken

The probability that in the sample fewer than 48​% say that having a flexible work schedule is either very important or extremely important to their career success is

The probability that in the sample between 33​% and 48​% say that having a flexible work schedule is either very important or extremely important to their career success is

The probability that in the sample more than 42% say that having a flexible work schedule is either very important or extremely important to their career success is

The labor force participation rate is approximately 63% in the US (i.e. approximately

63% of eligible adults actually work). Suppose 100 adults are randomly selected (assume

independence).

(a) Use the binomial distribution to find the probability that exactly 70 work.

(b) Use the normal approximation to find the probability that exactly 70 work.

(c) Use the normal approximation to find the probability that 70 or less work.

Wilson Publishing Company produces books for the retail market. Demand for a current book is expected to occur at a constant annual rate of 7,000 copies. The cost of one copy of the book is $13. The holding cost is based on an 16% annual rate, and production setup costs are $135 per setup. The equipment on which the book is produced has an annual production volume of 25,000 copies. Wilson has 250 working days per year, and the lead time for a production run is 17 days. Use the production lot size model to compute the following values:

Minimum cost production lot size. Round your answer to the nearest whole number. Do not round intermediate values. Q* =

Number of production runs per year. Round your answer to two decimal places. Do not round intermediate values.

Number of production runs per year =

Cycle time. Round your answer to two decimal places. Do not round intermediate values.

T = days

Length of a production run. Round your answer to two decimal places. Do not round intermediate values.

Production run length = days

Maximum inventory. Round your answer to the nearest whole number. Do not round intermediate values.

Maximum inventory =

Total annual cost. Round your answer to the nearest dollar. Do not round intermediate values.

Total annual cost = $

Reorder point. Round your answer to the nearest whole number. Do not round intermediate values.

r =

Questions A - F

A recent survey of 1000 American women between the ages of 45 and 64 asked them what medical condition they most feared. Of those sampled 61% said breast cancer, 8% said heart disease, and the rest picked other conditions. By contrast, currently about 3% of female deaths are due to breast cancer, whereas 32% are due to heart disease.

A. Construct a 95% confidence interval for the population proportion of women who most feared breast cancer.

In the 2006 General Social Survey, respondents were asked if they favored or opposed the death penalty for people convicted of murder. Of the 2815 who responded, 1885 were in favor of the death penalty.

B. Compute a point estimate for those in favor of the death penalty.

C. Construct a 99% confidence interval for the population proportion favoring the death penalty for people convicted of murder. Round the proportion to 3 decimal places (for example, 0.123 is a proportion to 3 decimal places).

D. Construct a 90% confidence interval for the population proportion favoring the death penalty for people convicted of murder. Round the proportion to 3 decimal places (for example, 0.123 is a proportion to 3 decimal places).

A March 2020 online survey of GVSU STA 215 students asked if they went to Florida during Spring Break week. Assume this convenience sample is a good representation of the GVSU student population. The 95% confidence interval to estimate the GVSU student population proportion who went to Florida is as follows: (0.151, 0.585). The sample size n = ?, p̂ = ?, and 1 − p̂ = ?. Find p̂, the sample proportion of GVSU students who went to Florida and find the margin of error (M.O.E.) for this estimate.

E. p̂ =

F. Margin of Error =

Could you please show me how to calculate the probability density function (pdf) e.g. the scaled frequency. You will need to give the absolute frequency, relative frequency and the
scaled frequency of the values below. Please show all working out. Please only answer if you are 100% sure you can solve it accurately and provide all of the correct working out.

Thank you

force (kN)                                                   Distance (m)      

2.11                                                                    2.33

2.33                                                                   3.42

3.02                                                                  3.13

3.02                                                                   1.32

7.83                                                                   0.53

4.40                                                                   4.12

1.48                                                                   3.67

1.40                                                                   4.98

4.81                                                                  2.34

1.53                                                                  1.04