An environmentalist wants to find out the fraction of oil tankers that have spills each month. In an earlier study, the population proportion was estimated to be 0.270.27.   How large a sample would be required in order to estimate the fraction of oil tankers that have spills each month at the 98%98% confidence level with an error of at most 0.030.03? Round your answer up to the next integer.

Q: There are 5000 observations in a data set. 10% of the data are “1”s, while the rest are “0”s. If we…

A: The data set consist of 5000 observations. The observations are 0's and 1's. An amount of data…

Q: You want to obtain a sample to estimate a population proportion. At this point in time, you have no…

A: Solution: From the given information, confidence level is 0.999 and E=0.05.

Q: Your professor wishes to estimate the proportion of high school students enrolled in college-level…

A: Given: margin of error of 3.5 percent 99% confidenp p= 18.3%

Q: A recent study indicated that 20% of 133 women over age 55 in the study were widows.  a. How large a…

A:

Q: Two sections of statistics are​ offered, the first at 8 a.m. and the second at 10 a.m. The 8 a.m.…

A: given , Two sections of statistics are​ offered, the first at 8 a.m. and the second at 10 a. m The 8…

Q: Over the break, you do some reasearch. In a random sample of 250 U.S. adults, 56% said they ate…

A:

Q: mpling process is repeated many time sers who use this social media platfor

A: Option b) is correct.   The estimate is given by p^ =0.458 + 0.5282 = 0.52

Q: n a population-based cohort study, an entire community was interviewed regarding smoking habits and…

A: Here the given table is   we have to Calculate the proper measure of association of smoking and lung…

Q: There are many reasons adults use credit cards. A recent survey found that 66% of adults used credit…

A: 66% of adults use credit cards for convenience.Confidence level is 99% i.e., 0.99.Margin of error is…

Q: you want to obtain a sample to estimate a population proportion. based on previous evidence, you…

A:

Q: A researcher wishes to estimate the number of households with two cars. How large a sample is needed…

A:

Q: A survey found that​ 79% of a random sample of 1024 American adults approved of cloning endangered…

A: It is given asSample proportion, p^ = 79% = 0.79Sample size,, p^ = 79% = 0.79Comfidence level = 90%

Q: Spending on concessions at the movies varies by age of the movie goer. A random sample of 100 adults…

A: It is given that the random sample of 100 adults, 70 purchased popcorn in their 40’s. Another sample…

Q: You are told that a survey produced a 90% confidence interval for the mean spent on utilities per…

A:

Q: A study shows that 93% of people prefer milk chocolate over dark chocolate. How large of a random…

A:

Q: n the year 1990 25% of students at a particular university received some sort of scholarship. The…

A: Given Data: p^=12/25=0.48n=25   Null and Alternate hypothesis: H0: p=0.25 Ha: p≠0.25

Q: The. Nielsen television ratings used a random sample of 2,000 homes and found that 45% of the homes…

A:

Q: A rare birth defect occurs in approximately 0.5% of all cases in males. If we sample all the males…

A: Given information: The total number of males born in 2016 in a specific region is N = 200,000. It is…

Q: A random sample of medical files is used to estimate the proportion p of all people who have blood…

A: Margin of error(E), E=z×p×qn From the above E, find n, n=zE2×p×q Here, E=0.04 There is no…

Q: A researcher wishes to estimate the number of households with two computers. How large a sample is…

A: given data   CI = 0.90, P ( - Z< P < Z ) = 0.90 therefore z = 1.645 ( =z table ) E = 6% =…

Q: A researcher claims that based on the information obtained, 17% of young people ages 9-19 are obese.…

A: Given : Sample size  of young people ages 9-19 (n) = 200 Let X: No. of young people ages 9-19 obese…

Q: Suppose that a test for presence of a disease is 87.5% accurate. Within a sample of 3200 patients,…

A: (1)   From the given information,   The incidence rate of disease = 14% The accuracy of test =…

Q: what range of raw scores makes up the middle 40%

A: The middle 40% means, the scores lie between 30th and 70th percentile. From stand normal, z-score…

Q: You want to estimate the percentage of small incorporated businesses that are owned by women. A…

A: The random variable percentage of small incorporated businesses follows binomial distribution. The…

Q: You would like to estimate the proportion of all residents in favor of a new law with 98%…

A: The sample proportion is 0.30, margin of error is 0.06, and the confidence level is 98%. Computation…

Q: Examining a random sample of records from my past Statistics classes, I found the 47 of the 282…

A:

Q: intended population

A: A population is the entire group that you want to draw conclusions about   Intended population:…

Q: USA Today reported that about 47% of the general consumer population in the United States is loyal…

A: From the provided information, 47% of the general consumer population in the United States is loyal…

Q: For a sample of n=16 scores, how many scores are used to calculate the sample variance?

A:

Q: A group of students need to submit a project and they need to survey people about their daily…

A: see the handwritten solution

Q: A researcher wants to do a study to see what the proportion of vaccinated people is in a certain…

A:

Q: (d) What height corresponds to the 95th percentile in the Galton study?

A:

Q: State the equation for the 95% confidence interval?

A: The equation for confidence interval can be stated as: Here x̅ is the sample mean, Zα/2 is the…

Q: In politics, marketing, etc. we often want to estimate a percentage or proportion p. One calculation…

A: Here the proportion of people liking dark chocolate is 37% with a margin of error 2.5%  So, the…

Q: You want to obtain a sample to estimate a population proportion. At this point in time, you have no…

A:

Q: you want to obtain a sample to estimate a population proportion. based on previous evidence, you…

A:

Q: A researcher wishes to estimate the number of households with two computers. How large a sample is…

A: population proportion (p) = 0.23 let, sample proportion = m and , number of samples to be collected…

Q: Find the sample size required to estimate the percentage of statistics students who take their…

A: The margin of error (E) is 0.02. The confidence level is 0.95.

Q: etermine what percent of pre-kindergarten children ages 3 to 5 whose mother had a bachelor's degree…

A: When we don't have any prior information about the population proportion, we generally take it as…

Q: Construct a 90% confidence interval of the population mean age for the college students in Example…

A: We have to find a...n , x̄, zc and E  b. Find the left and right endpoints of the confidence…

Q: - Parameter Statement - Hypotheses – Assumptions & Conditions - Name the Test - Test Statistic -…

A: For Males : we have the sample size is N1=1205N1 = 1205 , the number of males that have at-least one…

Q: You want to obtain a sample to estimate the proportion of a population that possess a particular…

A: The confidence level is 98% and the margin of error is 5%.

Q: You are a researcher studying a certain species of fish in a local lake. You gather a random sample…

A: