Math

StatisticsQ&A LibrarySuppose a lightbulb manufacturer claims that the mean lifetime of it's bulb is 35 hours. Assume the bulb lifetime have a mound shape distribution with standard deviation of 5 hours. If the manufacturer claim is true, what percent of the light bulbs will burn out in less than 20 hours?Question

Asked Jan 21, 2020

6 views

Suppose a lightbulb manufacturer claims that the mean lifetime of it's bulb is 35 hours. Assume the bulb lifetime have a mound shape distribution with standard deviation of 5 hours. If the manufacturer claim is true, what percent of the light bulbs will burn out in less than 20 hours?

Step 1

**68-95-99.7-rule:**

Let *X *be an observation from a normal distribution (mound shape), having mean µ and standard deviation σ, then according to the 68-95-99.7-rule, approximately 68%, 95% and 99.7% of the values lie within one, two and three standard deviations of the mean respectively. That is,

Step 2

The random variable follows mound distribution with mean 35 hours and standard devia...

Tagged in

Find answers to questions asked by student like you

Q: Identifying H0 and H1 In Exercises 5–8, do the following: a. Express the original claim in symbolic ...

A: Given that,Cell Phone Claim: Fewer than 95% of adults have a cell phone. In a Marist poll of 1128 ad...

Q: In Exercises 1–4, use these results from a USA Today survey in which 510 people chose to respond to ...

A: P-value method:In this method, compare the P-value with a significance level for testing the hypothe...

Q: Confidence Intervals. In Exercises 9–24, construct the confidence interval estimate of the mean. Spe...

A: Click to see the answer

Q: Tornadoes Listed below are the F-scale intensities of recent tornadoes in the United States. Constru...

A: From the given question,The frequency distribution is given by:

Q: The ages of a sample of Canadian tourists flying from Toronto to Hong Kong were 32, 21, 60, 47, 54, ...

A: Given that,32 21 60 47 54 17 72 55 33 41

Q: Graduation Rates. Refer to Exercise A.45. Use the technology of your choice to do the following. a. ...

A: a)Scatterplot matrix:Software procedure: Step by step procedure to draw scatterplot matrix using Min...

Q: Vision Correction About 75% of the U.S. population uses some type of vision correction (such as glas...

A: (a)Here, the vision correction uses rate is 75%.The probability that he or she does not use vision c...

Q: Black Cars Use subjective probability to estimate the probability of randomly selecting a car and ge...

A: In this context, the information about the colors of cars is not provided. So, consider as given bel...

Q: Lefties There have been several studies conducted in an attempt to identify ways in which left-hande...

A: From the given information,Confidence level (1-α) = 0.99Margin of error = 4.σ = 15.

Q: Touch Therapy When she was 9 years of age, Emily Rosa did a science fair experiment in which she tes...

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

Q: Sample Size Find the Sample size necessary to estimate the mean arrival delay time for all American ...

A: Population standard deviation, sigma is 30.4.The z-critical value for 95% confidence interval is 1.9...

Q: Quality Control After constructing a new manufacturing machine, five prototype integrated circuit ch...

A: Click to see the answer

Q: Bank Queues Waiting times (in seconds) of customers at the Madison Savings Bank are recorded with tw...

A: In this case we need to find the coefficient variation for the waiting times of customers in single ...

Q: The following data are from an experiment designed to investigate the perception of corporate ethica...

A: According to the provided data, three groups (management, research and advertising) are considered t...

Q: The data below are the monthly average high temperatures for New York City. What is the five-number ...

A: Five number summary of a dataset:The five number summary of any dataset contains the values of minim...

Q: Average The defunct website IncomeTaxList.com listed the “average” annual income for Florida as $35,...

A: Solution: We are given that:The defunct website IncomeTaxList.com listed the “average” annual income...

Q: Health Test In an investigation of a relationship between systolic blood pressure and diastolic bloo...

A: From the given question,For checking the which of given graphs are most useful or helpful when resea...

Q: IQ Scores Most people have IQ scores between 70 and 130. For $39.99, you can purchase a PC or Mac pr...

A: In this case, we need to check whether the result has statistical and practical significance.

Q: In a sales effectiveness seminar, a group of sales representatives tried two approaches to selling a...

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

Q: Type I and Type II Errors. In Exercise, identify expressions that identify the type I error and the ...

A: Click to see the answer

Q: Sales of LP Vinyl Record Albums Listed below are annual U.S. sales of vinyl record albums (millions ...

A: In this case we need to find the range, variance and standard deviation for the for the annual U.S s...

Q: Finding Sample Size to Achieve Power Researchers plan to conduct a test of a gender-selection method...

A: Click to see the answer

Q: Determining Sample Size. In Exercises 19–22, assume that each sample is a simple random sample obtai...

A: Table 7-2 shows that the minimum sample size needed, for a confidence level of 99% and a margin of e...

Q: Critical Thinking. In Exercises 17–28, use the data and confidence level to construct a confidence i...

A: The formula for point estimate is,

Q: TV Prices Listed below are selling prices (dollars) of TVs that are 60 inches or larger and rated as...

A: From the given problem, the selling prices of TV are not selected at random. Thus, the resulting sta...

Q: How do we denote the statistics used to estimate a. the y-intercept of the population regression pla...

A: a)Estimate of y-intercept:

Q: A statistics professor gives a survey to each of the 100 students in an introductory statistics lect...

A: Obtain the population standard deviation:

Q: Distributions Identify the distribution (normal, Student t , chi-square) that should be used in each...

A: The conditions for using t distribution in the estimate of confidence interval of mean is,The popula...

Q: Type I and Type I l Errors. In Exercises 29–32, provide statements that identify the type I error an...

A: Click to see the answer

Q: The amount of money spent weekly on cleaning, maintenance, and repairs at a large restaurant was obs...

A: Click to see the answer

Q: Police response time to an emergency call is the difference between the time the call is first recei...

A: Consider X be a random variable which follows normal distribution indicating the police response tim...

Q: Geometric Distribution If a procedure meets all the conditions of a binomial distribution except tha...

A: Define a random variable x as the number of subjects who is a universal donor. The number of subject...

Q: In a study conducted to investigate browsing activity by shoppers, each shopper was initially classi...

A: The critical value tc for 95% confidence level with sample size 24:The confidence level is 95%. That...

Q: A researcher is interested in determining whether age influences the level of depression experienced...

A: 1.The dependent variable is a variable or a characteristic of interest considered by the investigato...

Q: Hurricanes Listed below are the numbers of Atlantic hurricanes that occurred in each year. The data ...

A: In this case we need to find the range, variance and standard deviation for the numbers of Atlantic ...

Q: P -Values. In Exercises 17–20, do the following: a. Identify the hypothesis test as being two-tailed...

A: Given test statistic Z = -2.50Claim = p < 0.75Here the hypothesis test is left tailed as the clai...

Q: Caffeine in Soft Drinks Listed below are measured amounts of caffeine (mg per 12 oz of drink) obtain...

A: From the given problem, equal weight given to all brands. But some of these 20 brands are most prefe...

Q: Normality Requirement What does it mean when we say that the confidence interval methods of this sec...

A: If the condition of the normality is not satisfied, the confidence intervals methods are used in thi...

Q: In Exercises 9–22, use technology to create the large number of bootstrap samples. Old Faithful Use ...

A: a)Answers may vary. One of the possible answers is given below:

Q: Job Stress and Income Listed below are job stress scores and median annual salaries (thousands of do...

A: The claim that there is a correlation between job stress and annual income is the alternative hypoth...

Q: In the section we introduced a descriptive measure of the utility of the multiple linear regression ...

A: a)Coefficient of multiple determination:The coefficient of multiple determination is a descriptive m...

Q: Peas in a Pod Biologists conducted experiments to determine whether a deficiency of carbon dioxide i...

A: In this case we need to find the range, variance and standard deviation for the phenotype of peas.

Q: Constructing Normal Quantile Plots. In Exercises 17–20, use the given data values to identify the co...

A: The sample of arm circumferences (cm) of the females is 40.7, 44.3, 34.2, 32.5 and 38.5.Arrange the ...

Q: The calculations for a factorial experiment involving four levels of factor A, three levels of facto...

A: According to the provided information,

Q: Cell Phones and Brain Cancer In a study of 420,095 cell phone users in Denmark, it was found that 13...

A: a)Requirement check:

Q: Binomial Probability Formula. In Exercises 13 and 14, answer the questions designed to help understa...

A: Click to see the answer

Q: Good Sample? Given the sequence of data, if we fail to reject randomness, does it follow that the sa...

A: Here, if failed to reject the randomness, then the data is selected at random.

Q: In the following problem, check that it is appropriate to use the normal approximation to the binomi...

A: Click to see the answer

Q: What’s Wrong? USA Today published a list consisting of the state tax on each gallon of gas. If we ad...

A: Solution: We are given that:USA Today published a list consisting of the state tax on each gallon of...

Q: Chebyshev’s Theorem Based on Data Set 1 “Body Data” in Appendix B, blood platelet counts of women ha...

A: Chebyshev’s theorem: