2- We would like to survey a number of electric vehicles (EVs) to estimate the average distance EVs travel on a single charge of batteries. A previous similar study gave a sample standard deviation of 80 Kilometers. (A) How many EVs should we survey to be 95% confident that our sample mean will not deviate from the true average by more than 50 Kilometers. (B) How many EVs should we survey to be 95% confident that our sample mean will not deviate from the true average by more than 20 Kilometers.

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A: The mean is 1.5 and the standard deviation is 0.5 hours.

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A: From the given information Null Hypothesis: H0: The mean monthly balance of credit card holders is…

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A: we have given that  n1=250 ,n2=250 ,xbar1=391 ,xbar2=426 ,s1=20 ,s2=44 alpha=0.05

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A: “Since you have posted a question with multiple sub-parts, we will solve first three subparts for…

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A: We have given that  Sample size n=83 , sample mean = 90 Standard deviation = 15  Population mean =…

Q: Can you be 96% confident that there is a difference in the means of the two populations?

A: Here Take  For East Side plant Sample Size=n1=54 Sample mean=x1 = 5.3 Days Sample Sd=s1= 1.3 Days…

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A: Data given n1=245 , sample mean x̄1= 17.8 and s1= 4.3 n2=225, sample mean x̄2=18.2 amd s2= 3.60

Q: Suppose that Kitty studied for the Graduate Management Admission Test (GMAT) using a well-known…

A:

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A: Given, μ=375σ=25 Let X be the no. of vehicles passing through a certain intersection per day. Since…

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A: Given : sample size, n = 15

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A: Let, X=the number of vaccine μ =mean σ = sd

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Q: estimate is within .04 ounce of the population mean?

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A:

Q: On average, Americans have lived in 2 places by the time they are 18 years old. Is this average less…

A: Givensample mean(x)=1.97standard deviations(s)=0.2sample size(n)=40μ=2α=0.01

Q: a. Should they build the windmill? Justify by conducting a hypothesis test at α = 0.05. Report the…

A: here from given information  n = 35 sample mean = 21.4 mph sample standard deviation  = 5.4 mph…

Q: A researcher is conducting a study to determine the mean trough dosage of medication for a…

A: The following information is provided that is required to compute the sample size: Required…

Q: The average salary of bank managers in a certain city is $85,600 pesos per hour with a standard…

A:

Q: For a study conducted by the research department of a pharmaceutical company, 205 randomly selected…

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A: The aim is to check mothers working at a company providing daycare facilities will have less days…

Q: Do political science classes require more writing than history classes? The 50 randomly selected…

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Q: )  Suppose that in a random sample of 50 well water samples, conducted in particular region of Nova…

A: Solution

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A:

Q: 4.) In order to determine the effect of music on the speed of students in answering exams, an…

A:

Q: For a study conducted by the research department of a pharmaceutical company, 245 randomly selected…

A: Given  n1=245, x̄1=17.8, s1=4.3  n2=225, x̄2=18.2, s2=3.6

Q: During the winter of 2008-2009, the average utility bill for residents of a certain state was $181…

A: we have given that  n=30 ,xbar=173.51 ,18.91 and alpha =0.05

Q: a.     What statistical test will you use to test this data ?   b.     State the null and…

A: From provided information it is claimed that, women’s movement has resulted in an increase in the…

Q: 2 The FCC conducts broadband speed tests to measure how much data per second passes between a…

A: We have given that  Sample size n= 15 Population standard deviation = 12.2 Sample standard deviation…

Q: 3. The U.S. Department of Agriculture claims that the mean consumption of bottled water by a person…

A: Claim : the mean consumption of bottled water by a person in the United States is 28.5 gallons per…

Q: 2. The manufacturer of soap claims that the average weight of detergent soap per pack is 200 grams.…

A:

Q: A business consultant wanted to investigate whether providing daycare facilities on the company…

A: Hey, since there are multiple subparts posted, we will answer first three question. If you want any…

Q: A manufacturer claims that a particular automobile will get at least 50 miles per gallon on the…

A: Solution: Given: Sample size: n = 30 cars Population standard deviation: σ = 2.3 miles per gallon…

Q: 1. A pharmaceutical company says that the efficacy rate of their medicine is 90% and the standard…

A:

Q: A hospital president claims that the average Salary of registered nurses at her hospital is more…

A:

Q: ne hundred (900) high school freshmen were randomly selected for a national survey. Among survey…

A: Given data,Mean x=2.7sd     σ=0.4n=900What is the margin of error at 95% confidence level?

Q: lower

A: Given Mean = $ 92,300 Standard deviation = $ 32,000 (e) Standard deviation for n = 100 Standard…

Q: 4.) Suppose that you want to decide which of the two equally priced brands of light bulbs last…

A:

Q: If New York City has a mean gasoline price of $307 with a standard deviation of $19; while Hawaii…

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Q: Previously, an organization reported that teenagers spent 4.5 hours per week, on average, on the…

A: Here, Claim: Teenagers spent higher than 4.5                     hours per week,on average,on the…

Q: NebNas manages the credit department for a grocery store chain in the province, and she would like…

A: Given, The null hypothesis, H0:μ=95 The alternative hypothesis, H1:μ≠95 sample size, n=100 sample…

Q: Kurtis is a statistician who claims that the population mean annual salary of an employee in…

A: Test hypothesis:Denote the population mean annual salary of an employee in the city of Yarmouth as…

Q: A company would like to determine if there is a difference in the number of days that employees are…

A: It is given that, Number of employees in the sample from East side plant n1 = 54 Average missed days…

Q: erik, a tourism expert, is researching the number of overnight stays at two large hotels. He…

A: From the given information, Consider, n1=30μ1=135s1=22n2=22μ2=142s2=18

Q: So, if you were a researcher and you desired a small standard deviation of sample means (a "skinny"…

A: The standard deviation of sample mean is:        = ​σ​/√n,     where n is the sample size

Q: An online stock trading company makes part of their revenue from clients when the clients trade…

A: Givensample size(n)=98Mean(x)=85standard deviation(s)=17α=10%=0.10

Q: A travel analyst claims that the mean price of a round trip flight from New York City to Los Angeles…

A: Solution:

Q: An online stock trading company makes part of their revenue from clients when the clients trade…

A: In the given problem we have,  n = sample size = 120 The average number of trades per year was 82…

Q: 4. The city manager has received complaints that local firefighters are underpaid. He gathers a…

A: Let X denotes salary of firefighter. The sample size is n=120.  Let μ denotes the average salary of…