A sample of 42 chemists from Washington state shows an average salary of $39,420 with a standard deviation of $1659, while a sample of 36 chemists from New Mexico has an average salary of $30,215 with a standard deviation of $4116. a. Is there a significant difference between the two states in chemists’ salaries at α = 0.02? b. Find the 98% confidence interval of the difference in the means.
Q: A random sample of 76 eighth grade students' scores on a national mathematics assessment test has a…
A: given data claim : μ > 285n = 76x¯ = 292σ = 30α = 0.15
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A: The objective of this question is to test the manufacturer's claim that the calling range of its…
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A:
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A: Consider, the pooled variance, spooled2=(n1-1)s12+(n2-1)s22n1+n2-2…
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A: Given,sample size(n)=35sample mean(x¯)=$25,226standard deviation(s)=$3251α=0.01
Q: A manufacturer claims that the calling range (in feet) of its 900-MHz cordless telephone is greater…
A: From the provided information,
Q: The body temperatures of two species of geckos were measured. The n 14 geckos from species A had a…
A: The pooled variance is, sp2=n1-1s12+n2-1s22n1+n2-2=14-10.812+11-10.75214+11-2=0.6154 The pooled…
Q: A manufacturer claims that the calling range (in feet) of its 900-MHz cordless telephone is greater…
A: The objective of this question is to determine whether the results support the manufacturer's claim…
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: p value is less than 0.05Explanation:
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A: Given : The above parameters belong to the population Therefore, Population mean , μ = 0.73…
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: The objective of this question is to formulate the null and alternative hypotheses for a statistical…
Q: Zappos is an online retailer based in Nevada and employs 1,300 employees. One of their competitors,…
A: Denote μ as the true average age of a Zappos employee.
Q: The average salary for American college graduates is $45,900. You suspect that the average is more…
A: The test statistic is obtained by the formula is z=x¯-μ0σn z=47317-45900716046=1.342 The critical…
Q: Step 2 of 4: Compute the value of the test statistic. Round your answer to two decimal places.
A: The value of the test statistic is, t=x¯1-x¯2s12n1+s22n2=55-5814.0281+13.7281=-32.1764=-1.3784≈-1.38
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: The objective of this question is to test the claim that the braking distance for SUVs equipped with…
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A: For the parameter, μ as the true average hour spent by American teenagers, under the alternate…
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: The objective of this question is to compute the value of the test statistic in a hypothesis test…
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A: We have given, The sample size: n=35 The sample mean: x¯=3.17 days The sample standard deviation:…
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A: Given data: Population mean = $ 40000 Sample size = 20 Sample mean = $ 43228 Sample standard…
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A: For call center A, The sample size is The sample mean is The sample standard deviation is For call…
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A: We have given that Sample sizes n1= 40 , n2= 35 Sample means xbar1= 3.2 , xbar2=1.9 Standard…
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A:
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: The objective of this question is to compute the value of the test statistic in a hypothesis test…
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A: Here Given FOR TUESDAY EVENING Sample size=n1=33 Sample mean= 5490=X1 Population SD=610=σ1 Now…
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A:
Q: The average gasoline price of one of the major oil companies has been $2.90 per gallon. Because of…
A: given dataclaim : μ<2.90n = 36x¯=2.83σ=0.19
Q: The salaries of professional baseball players are heavily skewed right with a mean of $3.2 million…
A: The sample standard deviations are s1=2 and s2=1.5.
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A: Given information: The hypothesized population mean is μ=569. The sample size is n=40. The sample…
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A: Given that sample mean= x= 654.16 Population standard deviation= σ = 164.43 n=sample size= 50…
Q: A random sample of 81 eighth grade students' scores on a national mathematics assessment test has a…
A:
Q: Step 1 of 4: State the null and alternative hypotheses for the test.
A: The claim of the test is that the braking distance for SUVs equipped with tires using compound 1 is…
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A: Claim : mean of no more than 250 W.
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: sample mean for compound 1, x̄1 = 68 feetpopulation standard deviation for compound 1, σ1 = 13.9…
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: Step 1: State the given: sample mean for compound 1, x̄1 = 68 feetpopulation standard deviation for…
Q: The Medical Rehabilitation Education Foundation reports that the average cost of rehabilitation for…
A: Givensample size(n)=35Mean(x¯)=26343standard deviation(s)=3251α=0.01claim is the average cost of…
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A:
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: The given data informations are,Mean breaking strength for SUVsPopulation standard deviationSample…
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: It is required to test whether the braking distance for SUVs having tires made with compound 1 is…
Q: A random sample of 76 eighth grade students' scores on a national mathematics assessment test has a…
A: Given data is appropriate for testing of hypothesis . to test z-test for single mean . Because it is…
Q: A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed…
A: The objective of this question is to find the p-value associated with the test statistic in a…
Q: A manufacturer claims that the calling range (in feet) of its 900-MHz cordless telephone is greater…
A: Suppose denotes the true population mean range of the manufacturer’s cordless telephone and…
Q: In a random sample of 75 eighth grade students scores on a national mathematics assessment test has…
A: GivenMean(x) = 266sample size(n)=75standard deviation(σ)=34α=0.09
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- A researcher claims that the average number of calories in a serving of ice cream is 70 with a population standard deviation of 7. A sample of 40 servings of ice cream was found to be different with an average of 73 calories. Check the researcher’s claim at α = 0.05 and compute the test value.A state school administrator says that the standard deviation OT SAI critical reading test scores is 114. A random sample of 19 SAT critical reading test scores has a standard deviation of 143. At α = 0.10, is there enough evidence to reject the school administrator's claim? Assume the population is normally distributed.Suppose the average size of a new house built in a certain county in 2014 was 2,270 square feet. A random sample of 25 new homes built in this county was selected in 2018. The average square footage was 2,191, with a sample standard deviation of 223 square feet. Complete parts a and b. Using α=0.02, does this sample provide enough evidence to conclude that the average house size of a new home in the county has changed since 2014? Determine the null and alternative hypotheses.
- Zappos is an online retailer based in Nevada and employs 1,300 employees. One of their competitors, Amazon.com, would like to test the hypothesis that the average age of a Zappos employee is less than 36 years old. A random sample of 22 Zappos employees was found to have an average age of 33.9 years. The standard deviation for this sample was 4.1 years. Amazon would like to set α = 0.025. The correct hypothesis statement for this hypothesis test would be A) H0: μ = 33.9; H1: μ ≠ 33.9. B) H0: μ = 36; H1: μ ≠ 36. C) H0: μ ≤ 36; H1: μ > 36. D) H0: μ ≥ 36; H1: μ < 36.A farmer claims that the average fat content in his chickens is 29 g. A researchertested 36 chickens from this farm and found that the average fat content was30.1g with standard deviation of 3.8 g. Is there enough evidence to reject theclaim at α = 0.1?The U.S. average for state andlocal taxes for a family of four is $4251. A randomsample of 20 families in a northeastern state indicatesthat they paid an annual amount of $4654 with astandard deviation of $950. At a=0.1, is theresufficient evidence to conclude that they pay more thanthe national average of $4251?
- A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed to reduce braking distances for SUVs equipped with the tires. The mean braking distance for SUVs equipped with tires made with compound 1 is 65 feet, with a population standard deviation of 13.6. The mean braking distance for SUVS equipped with tires made with compound 2 is 69 feet, with a population standard deviation of 8.5. Suppose that a sample of 55 braking tests are performed for each compound. Using these results, test the claim that the braking distance for SUVs equipped with tires using compound 1 is shorter than the braking distance when compound 2 is used. Let μ₁ be the true mean braking distance corresponding to compound 1 and μ₂ be the true mean braking distance corresponding to compound 2. Use the 0.05 level of significance. Step 3 of 5 Find the p-value associated with the test statistic. Round your answer to four decimal places. Answer How to enter your answer (opens in…A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed to reduce braking distances for SUVs equipped with the tires. The mean braking distance for SUVS equipped with tires made with compound 1 is 68 feet, with a population standard deviation of 13.9. The mean braking distance for SUVs equipped with tires made with compound 2 is 73 feet, with a population standard deviation of 13.7. Suppose that a sample of 72 braking tests are performed for each compound. Using these results, test the claim that the braking distance for SUVS equipped with tires using compound 1 is shorter than the braking distance when compound 2 is used. Let μ, be the true mean braking distance corresponding to compound 1 and μ₂ be the true mean braking distance corresponding to compound 2. Use the 0.05 level of significance. Step 1 of 5: State the null and alternative hypotheses for the test.According to a money report by a government institution, 18-to-20-year-old college students have an average credit card balance of $569. A researcher wants to find out if this number is lower now and collects data for a random sample of 40 college students. Their average credit card debt was found to be $535 with a sample standard deviation of $67.19. Complete parts a through c. Using α=0.05, does this sample provide enough evidence to conclude that the average credit card balance of 18-to-20-year-old college students has decreased since 2016? *Determine the null and alternative hypotheses. *Determine the appropriate critical value. Select the correct choice below and fill in the answer box within your choice. (Round to three decimal places as needed.) *Calculate the appropriate test statistic. *State the conclusion. Reject or Accept? Does changing the value of alphaα from .05 to 0.01 affect the conclusion? Why or why not? (Round to three decimal places as needed.)
- A researcher claims that the average life span of mice can be extended when the calories in their diet are reduced by approximately 40% from the time they are weaned. The restricted diets are enriched to normal levels by vitamins and protein. Suppose that a sample of 10 mice is fed a normal diet and has anaverage life span of 32.1 months with a standard deviation of 3.2 months, while a sample of 15 mice is fed the restricted diet and has an average life span of 37.6 months with a standard deviation of 2.8 months. Assume the distributions of life spans for the regular and restricted diets are approximately normal withequal variance.(a) State the appropriate hypotheses to test the researcher’s claim.(b) Conduct the test at the 0.05 level of significance. What do you conclude?A researcher compares two compounds (1 and 2) used in the manufacture of car tires that are designed to reduce braking distances for SUVs equipped with the tires. The mean braking distance for SUVs equipped with tires made with compound 1 is 65 feet, with a population standard deviation of 13.6. The mean braking distance for SUVs equipped with tires made with compound 2 is 69 feet, with a population standard deviation of 8.5. Suppose that a sample of 55 braking tests are performed for each compound. Using these results, test the claim that the braking distance for SUVs equipped with tires using compound 1 is shorter than the braking distance when compound 2 is used. Let μ₁ be the true mean braking distance corresponding to compound 1 and μ₂ be the true mean braking distance corresponding to compound 2. Use the 0.05 level of significance. Step 5 of 5: State the conclusion of the hypothesis test. Answer Tables Keypad Keyboard Shortcuts Previous Step Answers There is sufficient evidence…The salaries of professional baseball players are heavily skewed right with a mean of $3.2 million and a standard deviation of $2 million. The salaries of professional football players are also heavily skewed right with a mean of $1.9 million and a standard deviation of $1.5 million. A random sample of 40 baseball players’ salaries and 35 football players’ salaries is selected. The mean salary is determined for both samples. Let represent the difference in the mean salaries for baseball and football players. Which of the following represents the shape of the sampling distribution for ? skewed right since the populations are both right skewed skewed right since the differences in salaries cannot be negative approximately Normal since both sample sizes are greater than 30 approximately Normal since the sum of the sample sizes is greater than 30