Suppose that the times required for a cable company to ﬁx cable problems in its customers’ homes are uniformly distributed between 40 minutes and 65 minutes.(a) What is the probability that a randomly selected cable repair visit will take at least 50 minutes? (b) What is the probability that a randomly selected cable repair visit will take at most 55 minutes? (c) What is the expected length of the repair visit? (d) What is the standard deviation?
Describe when a z-test should be performed as opposed to a t-test? Which (if any) can we use all the time? Why or why not?Your manager, who just read an abridged version of a statistics book, wants you to test hypotheses for the difference in two population means. The sample sizes for each are 23. He is adamant that you perform a z-test. What would you tell him? What specific explanation would you give?
Information from the American Institute of Insurance indicates the mean amount of life insurance per household in the United States is $110,000. This distribution is positively skewed. The standard deviation of the population is not known.a. A random sample of 50 households revealed a mean of $112,000 and a standard deviation of $40,000. What is the standard error of the mean?b. Suppose that you selected 50 samples of households. What is the expected shape of the distribution of the sample mean?c. What is the likelihood of selecting a sample with a mean of at least $112,000?d. What is the likelihood of selecting a sample with a mean of more than $100,000?e. Find the likelihood of selecting a sample with a mean of more than $100,000 but less than $112,000.
Among the tools (e.g., graphics tools, knowledge-based tools, etc.) that the author discussed in the textbook, determine the type of tool that you would use for process improvement framework. Next, determine the type of tool you would use for problem solving framework. Justify your response.
suppose the probability that a carton of eggs will contain at least one broken egg is 1/3. use a simulation of 20 trials to find the probability that the next three cartons will contain only unbroken eggs
The number of choco chips in an 18 ounce bag of chocolate chip cookies is approximately normally distributed with a mean of 1256 and a standard deviation of 129 chips, What is the probability that a randomly selected bag contains fewer than 1000 chocolate chips?
John, one of the owners of Mi Casa Front Porch Restaurant has been working with the Chef, Maria to potentially add a new item to the menu. He sampled 50 of his regular customers and asks them if they would like the new item on the menu, 37 said yes and 13 said no. Determine the sample proportions of customers that would like the new item on the menu and determine the standard error of the proportion. How would this standard error influence John’s decision?Answer the questions below in essay format. Your essay must include an introduction, a body, and a conclusion, and it must address all relevant parts of each question. Your response should be a minimum of 150 words in length and include both the appropriate statistics and support for the analysis and interpretation. Make sure to cite any source you use. Proper citation format for a source includes the name of the author(s), the title of the work, the date of the publication, and the page number if you directly quote the source.Using the scenario above, identify the standard error of the proportion and determine the impact of the error on potential decision making by Mi Casa Front Porch Restaurant leaders.What should the company do based on the information calculated?
the mean sat verbal score is 401, with a standard deviation of 97. Use the empirical rule to determine what percent of the scores lie between 207 and 498. (assume the data set has a bell-shaped distribution)
Let X bar be the mean of a random sample from the exponential distribution.a) show that xbar is unbiasedpoint estimator of θb) using the mgf technique,determine the distribution of xbarc) use (b) to show that Y= 2nx bar/ θ has x^2 (chi) distibution with 2n degrees of freedom.d) based on part (c),find a 95 % confidence interval for θ if n=10
202001015013000113209700835073001400099401120010750624012700743013500139004200675067009330131859200214001138010800What is the 95% confidence interval estimate for the mean ticket sales revenueper theather? Interpret this result.