A company produces batteries whose lifetimes are normally distributed with a mean of 100 hours. It...
Fantastic news! We've Found the answer you've been seeking!
Question:
Transcribed Image Text:
A company produces batteries whose lifetimes are normally distributed with a mean of 100 hours. It is known that 96% of the batteries last at least 40 hours. Throughout this question all answers should be given correct to one decimal place. (а) If P(z > a) = 0.96, use normal distribution tables to find the value of 'a'. a = (b) Estimate the standard deviation lifetime. (c) Calculate the percentage of batteries that will last less than 57 hours. The company is liable to replace any battery which lasts for less than 40 hours. The company wishes to reduce the percentage of defective batteries from the current level of 4% to 2%. (d) (i) Use normal tables to find the value 'b' such that P(z < b) 2%. (ii) The company can use a chemical procedure which changes the values of the mean and standard deviation. If the standard deviation is set at 35 hours, find the mean lifetime which will reduce the percentage of defectives to 2%. A company produces batteries whose lifetimes are normally distributed with a mean of 100 hours. It is known that 96% of the batteries last at least 40 hours. Throughout this question all answers should be given correct to one decimal place. (а) If P(z > a) = 0.96, use normal distribution tables to find the value of 'a'. a = (b) Estimate the standard deviation lifetime. (c) Calculate the percentage of batteries that will last less than 57 hours. The company is liable to replace any battery which lasts for less than 40 hours. The company wishes to reduce the percentage of defective batteries from the current level of 4% to 2%. (d) (i) Use normal tables to find the value 'b' such that P(z < b) 2%. (ii) The company can use a chemical procedure which changes the values of the mean and standard deviation. If the standard deviation is set at 35 hours, find the mean lifetime which will reduce the percentage of defectives to 2%.
Expert Answer:
Related Book For
Statistical Reasoning for Everyday Life
ISBN: 978-0321817624
4th edition
Authors: Jeff Bennett, Bill Briggs, Mario F. Triola
Posted Date:
Students also viewed these accounting questions
-
If freeway speeds are normally distributed with a mean of = 70 mph and = 7 mph, find the probability that the speed of a randomly chosen vehicle (a) Exceeds 78 mph; (b) Is between 65 and 75 mph;...
-
The lengths of pregnancies are normally distributed with a mean of 268 days and a standard deviation of 15 days. a. One classical use of the normal distribution is inspired by a letter to Dear Abby...
-
IQ scores are normally distributed with a mean of 100 and a standard deviation of 16. Assume that many samples of size n are taken from a large population of people and the mean IQ score is computed...
-
Over 90 percent of the energy dissipated by an incandescent light bulb is in the form of heat, not light. What is the temperature of a vacuum-enclosed tungsten filament with an exposed surface area...
-
Why must women be targeted for assistance in the development process? Why is it important that all beneficiaries of development policies and programs be active participants in the design and...
-
A suggested format for the Letter of Representation has been sent by the auditors to the directors of Crighton-Ward. The directors have stated that they will not sign the Letter of Representation...
-
Madge does not keep full accounting records, but the following information is available in respect of her accounting year ended 31 March 2009: In her profit and loss account for the year ended 31...
-
Use the following information to determine this companys cash flows from investing activities. a. Equipment with a book value of $72,500 and an original cost of $158,000 was sold at a loss of...
-
SU and VT are chords that intersect at point R. S What is the length of line segment VT? O 4 units O 8 units O 13 units O 14 units V x+6 x+1 R x+4 T U
-
At the end of the fiscal year, the Precision Computer Centre has a $21,620 balance in Accounts Receivable. Here is a current schedule of accounts receivable: Assignment Although Accu Pacs account is...
-
Read the Daniel Terris book. This will include an overview of Lockheed Martins organization and will lay out the research plan that Terris used to obtain information necessary for his work. This will...
-
Assume a block cipher which operates on 4-bit blocks written as hexadecimal digits. For a particular key K it implements the following "encryption" on message m: m 0 1 2 3 4 5 5 C 7 e 6 7 8 9 a 2 a 4...
-
Cherry Inc. has forecast its sales for the coming months as follows: Standard Units Economy Units April 2 3 6 1 8 6 May 2 6 6 1 9 6 June 3 0 6 2 1 6 July 3 3 6 2 3 6 Cherry maintains finished goods...
-
Aqua Accessories plc . is a subsidiary company of River Recreation plc , and manufactures three products Sun Parasols, Deck Chairs, Buckets and Spades. The selling price, variable and fixed costs per...
-
On January 1, 2018, Canseco Plumbing Fixtures purchased equipment for $40,000. Residual value at the end of an estimated four-year service life is expected to be $4,000. The company expects the...
-
On April 1 of the current year, TJ's uncle gave her land that he had purchased several years ago for $30,000. The land was worth $20,000 at the time of the gift. TJ sold the land on December 1 of the...
-
Problem 2-1A (Algo) Preparing and posting journal entries; preparing a trial balance LO A1, P1 Karla Tanner opened a Web consulting business called Linkworks and completed the following transactions...
-
Distinguish between the work performed by public accountants and the work performed by accountants in commerce and industry and in not-for-profit organisations.
-
Use Table 5.1 to find the P-value that corresponds to the standard z-score, and determine whether the alternative hypothesis is supported at the 0.05 significance level. -0.4 for H a : u < 25...
-
What is blinding, and why is it important in an experiment to test the effectiveness of a drug?
-
The stack plot in Figure 3.25 shows Congressional Budget Office data for actual (through 2011) and projected spending on entitlement programs through 2085 as percentages of the gross domestic product...
-
Oswego Corporation reported net income $24,000; net sales $400.000; and average assets \($600,000\) for 2002. What is the 2002 profit margin? (a) 6%. (b) 12%. (c) 40%. (d) 200%.
-
Which measure is an evaluation of a company's ability to pay current liabilities? (a) Acid-test ratio. (b) Current ratio. (c) Both (a) and (b). (d) None of the above.
-
Which of the following is generally not considered to be a limitation of financial analysis? (a) Use of ratio analysis. (b) Use of estimates. (c) Use of cost. (d) Use of alternative account- ing...
Study smarter with the SolutionInn App