According to data from the 2010 United States Census, 43.1% of Americans over the age of 65 were male. Suppose Maria, a researcher, takes a random sample of 60 Americans over the age of 65 and finds that 18 are male. Let ?̂ p^ represent the sample proportion of Americans over the age of 65 that were male. What are the mean and standard deviation of the sampling distribution of ?̂ p^? Provide your answer rounded to three decimal places.

Q: The average American consumes 8.7 liters of alcohol per year. Does the average college student…

A: Given: The average American consumes 8.7 liters (μ0) of alcohol per year. Let n denote the number of…

Q: The sample mean weight of 65 adult African elephants was measured to be 14,325.62 pounds, with a…

A: Given information: x=14325.62 σ=872.71 n=65 Level of significance = 10%

Q: The incubation time for Rhode Island Red chicks is normally distributed with mean of 30 days and…

A: According to empirical rule (Also known as 68-95-99.7 rule):

Q: Question 32 Problem in photo!

A: Computation of proportion of women have total serum cholesterol levels exceeding 200:Here, the mean…

Q: According to a report published by the USDA 2 years ago, a typical American consumes an average of…

A: Given: Population mean = 31.1 Sample size = 64 Sample mean = 31.65 Sample standard deviation = 2.915…

Q: A recent survey was conducted to compare the cost of solar energy to the cost of gas or electric…

A:

Q: A New York Times article noted that the mean life span for 30 male symphony conductors was 78.1…

A: Givensample size(n)=30Mean(x)=78.1standard deviation(s)=8.6α=0.05

Q: In the same blood pressure study described previously, the systolic blood pressure for men and women…

A: According to the given information, we have The systolic blood pressure for men and women grouped…

Q: Suppose that IQ scores have a bell-shaped distribution with a mean of 100 and a standard deviation…

A: The mean is 100 and the standard deviation is 15.

Q: The sample mean weight of 100 chimpanzees was measured to be 82.4 pounds, with a standard deviation…

A:

Q: A New York Times article noted that the mean life span for 35 male symphony conductors was 73.4…

A: The test hypotheses are: Null hypothesis: H0: μ = 69.5 years Alternative hypothesis: H1: μ > 69.5…

Q: It is claimed that the average life span of people in a rural area is more than 64 years with a…

A: Given : population average (μ)=64standard deviation (σ) = 3Sample size (n) = 250 Sample mean (…

Q: Suppose that IQ scores have a bell-shaped distribution with a mean of 100 and a standard deviation…

A: Mean = 100 Standard deviation = 15

Q: Suppose that grade point averages of undergraduate students at one university have a bell-shaped…

A: According to the given information, we have Mean = 2.52 Standard deviation = 0.38

Q: A person must score in the upper 2% of the population on an IQ test to qualify for membership in…

A: Normal distribution is a continuous distribution which has many real life applications. Normal curve…

Q: recent study compared the time spent together by single- and dual-earner couples.  According to the…

A: Given : Claim : The single-earner couples on average spend more time watching television together.

Q: Based on data from the u.s. census, the mean age of college students in 2011 was 25 years, with a…

A: Given that: X is normal Distributed with mean µ = 25.0 and standard deviation σ = 9.5 By using…

Q: A study on the latest fad diet claimed that the amounts of weight lost by all people on this diet…

A:

Q: An economist would like to estimate the mean amount of money that a family spends to within $45. If…

A: GivenMargin of Error(E)-45standard deviation(σ)=190α=1-0.93=0.07α2=0.035zα2=1.8119      (from z…

Q: Suppose that IQ scores have a bell-shaped distribution with a mean of 100100 and a standard…

A: Empirical rule: About 68% of data lies within the first standard deviation of the mean. About 95%…

Q: Suppose that shoe sizes of American women have a bell-shaped distribution with a mean of 8.358.35…

A: The provided information are: Population mean (µ) = 8.35 Population standard deviation (σ) = 1.46

Q: Suppose that grade point averages of undergraduate students at one university have a bell-shaped…

A: Empirical rule: The probability that the observation under the normal curve lies within 1 standard…

Q: Suppose that grade point averages of undergraduate students at one university have a bell-shaped…

A: From the provided information, Mean (µ) = 2.61 Standard deviation (σ) = 0.44

Q: According to a report published by the USDA 4 years ago, a typical American consumes an average of…

A:

Q: In a sample of 240 workers, in a factory the mean and standard deviation of wages were $ 113.50 and…

A:

Q: The average grade of second year Business Management students in a certain college is normally…

A: Given: X¯=84, σ=5, α=0.10 Formula for interval is, Interval=X¯± Zασ From the statistical table…

Q: From historical records, we know that the standard deviation of starting salaries is $17,000. For…

A: Calculate the width of the given confidence interval.

Q: The average weekly income of a U.S. student worker is $200 with a standard deviation of 50. If a…

A: Standard error of sample mean=σn, where σ is the population standard deviation and n is the sample…

Q: The scores of individual students on a national test have a normal distribution with mean 18.6 and…

A: Given that  X~N(μ= 18.6 , σ= 5.9 ) μ= 18.6  , σ= 5.9 , n= 76

Q: town, the systolic blood pressure is normally distributed with a mean of 135 and a standard…

A: Given: μ=135, σ=9 The corresponding z-value needed to be computed: If a male is randomly selected…

Q: During the last week of the semester, students at a certain college spend on average 4.5 hours using…

A: Given,   Mean = 4.5 Standard deviation = 1.6 Sample size = 64   The objective is to find the…

Q: A random sample of 100 women each from the rural and urban  areas showed the following mean and…

A: Null Hypothesis: A hypothesis which is tested for plausible rejection is called the Null Hypothesis…

Q: A survey among freshmen at a certain university revealed that the number of hours spent studying the…

A: The random variable X is defined as the number of hours spent studying the week before final exams…

Q: The length of time required to complete a college achievement test is found to be normally…

A: From the given information, length of time required to complete a college achievement test follows…

Q: An economist would like to estimate the mean amount of money that a family spends to within $30. If…

A:

Q: What can be concluded at the the αα = 0.10 level of significance?

A: Given that  The average American consumes 86 liters of alcohol per year Population mean (μ) = 86…

Q: Suppose that shoe sizes of American women have a bell-shaped distribution with a mean of 8.12 and a…

A:

Q: For a population with mean 229.19 and standard deviation 32.63, what is the value of the standard…

A:

Q: The shelf life of a battery produced by one major company is known to be Normally distributed, with…

A:

Q: The CEO of battery manufacturing company claims that an average battery lasts 300 days. A researcher…

A: Given n=sample size=15, sample mean x̄=290, population mean μ=300 , sample standard deviations s=50…

Q: A researcher would like to estimate the mean amount of money that a family spends to within $75. If…

A: Determine the sample size.   The sample size is obtained below as follows:

Q: The U.S. Census (2000) reports that Americans spend an average of 24.3 minutes commuting to work…

A: It is given that the commuting time follows normal distribution with mean 24.3 minutes and standard…

Q: Suppose that grade point averages of undergraduate students at one university have a bell-shaped…

A:

Q: A half-century ago, the mean height of women in a particular country in their 20s was 63.7 inches.…

A: We have to find probability for sampling distribution of sample mean (x¯) Sampling distribution of…

Q: A placement test for the state university freshmen has a normal distribution with a mean of 700 and…

A: Let X  be the test score. It is given that , a placement test for the state university freshmen has…

Q: An economist would like to estimate the mean amount of money that a family spends to within $35. If…

A:

Q: The honors program at Brad's university only accepts students with an entrance exam score over 400.…

A: From the provided information, Mean (µ) = 250 Standard deviation (σ) = 80 Let X be a random variable…

Q: Suppose a random survey is conducted of 21 U.S. mothers who recently weaned their children. The mean…

A: Given data: A random survey contains n = 21 U.S. mothers who recently weaned their children. Sample…

Q: According to data from the U.S. Army the average foot length of women as normally distributed with a…

A: The random variable x represents foot lengths of women. x follows normal distribution with a mean of…

Q: A leading magazine (like Barron's) reported at one time that the average number of weeks an…

A: Given data,μ=35.2σ=5.6

Confidence Intervals

When we calculate intervals in probability and statistics, it can be simply termed as finding out a confidence interval. The confidence interval is usually calculated from the data set which is observed. The value of the parameter that needs to be calculated is present here only.