27. A company finds that the useful life of its computers is normally distributed with a mean of 3.5 years and a standard deviation of 0.4 years. Historically 50% of the computers have a useful life less than the computer manufacturer's advertised life. What is the manufacturer's advertised life for the computers 3.500 years O 325 years O 3.192 years 2975 years

27. A company finds that the useful life of its computers is normally distributed with a mean of 3.5 years and a standard deviation of 0.4 years. Historically 50% of the computers have a useful life less than the computer manufacturer's advertised life. What is the manufacturer's advertised life for the computers 3.500 years O 325 years O 3.192 years 2975 years

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

9. The number of births per woman in China is 1.6 down from 5.91 in 1966. This fertility rate has been attributed to the law passed in 1979 restricting births to one per woman. Suppose that a group of students studied whether or not the standard deviation of births per woman was greater than 0.75. They asked 50 women across China the number of births they had had. The results are shown in the following table. Does the students’ survey indicate that the standard deviation is greater than 0.75? Use α = 0.01. # of Births Frequency 0 5 1 30 2 10 3 5
Suppose that the quarterly sales levels among health care information systems companies are approximately normally distributed with a mean of 12 million dollars and a standard deviation of 1.3 million dollars. One health care information systems company considers a quarter a "failure" if its sales level that quarter is in the bottom 20% of all quarterly sales levels. Determine the sales level (in millions of dollars) that is the cutoff between quarters that are considered "failures" by that company and quarters that are not. Carry your intermediate computations to at least four decimal places. Round your answer to one decimal place. million dollars X S
Times for a surgical procedure are normally distributed. There are two methods. Method A has a mean of 35 minutes and a standard deviation of 3 minutes, while method B has a mean of 39 minutes and a standard deviation of 1.5 minutes. Which procedure is preferred if the procedure must be completed within 34 minutes? Which procedure is preferred if the procedure must be completed within 40.0 minutes? Which procedure is preferred if the procedure must be completed within 43 minutes?
Suppose that the quarterly sales levels among health care information systems companies are approximately normally distributed with a mean of 9 million dollars and a standard deviation of 1.4 million dollars. One health care information systems company considers a quarter a "failure" if its sales level that quarter is in the bottom 10% of all quarterly sales levels. Determine the sales level (in millions of dollars) that is the cutoff between quarters that are considered "failures" by that company and quarters that are not. Carry your intermediate computations to at least four decimal places. Round your answer to one decimal place.
12. (Two Samples) According to a survey, the mean price of gasoline in the United States was $1.20 per gallon in 1995 and $1.10 per gallon in 1994. (U.S. News & World Report, June 12, 1995). Suppose these means were based on random samples of 100 gasoline stations for 1995 and 120 gasoline stations for 1994. Also, assume that the sample standard deviations were $0.11 for 1995 and $0.10 for 1994. a. Construct a 98% confidence interval for the difference between the mean gasoline prices for 1995 & 1994. b. Test at the 1% significance level if the mean gasoline price was higher in 1995 than in 1994.
One year the ACT had a mean score of 22.7 and a standard deviation of 4.1. minutes. (a)Calculate the z-score of an ACT score of 25. Interpret it using a complete sentence. B. What ACT score is 1.5 standard deviations above the mean? What can you say about this consumption
Suppose that the quarterly sales levels among health care information systems companies are approximately normally distributed with a mean of 8 million dollars and a standard deviation of 1.3 million dollars. One health care information systems company considers a quarter a "failure" if its sales level that quarter is in the bottom 10% of all quarterly sales levels. Determine the sales level (in millions of dollars) that is the cutoff between quarters that are considered "failures" by that company and quarters that are not. Carry your intermediate computations to at least four decimal places. Round your answer to one decimal place. 00 0 million dollars X S ? Check acer Q tab esc ! 1 9. a @ 2 W →> S #m 3 X e C d $ LAS 4 C r % 5 f t > < 6 g y & JX b 7 h C n K1300
In Professor Krugman’s economics course, the correlation between the students’ total scores prior to the final examination and their final‑examination scores is ?=0.5.r=0.5. The pre‑exam totals for all students in the course have mean 280280 and standard deviation 40.40. The final‑exam scores have mean 7575 and standard deviation 8.8. Professor Krugman has lost Julie’s ﬁnal exam but knows that her total before the exam was 300.300. He decides to predict her ﬁnal‑exam score from her pre‑exam total. (a) Which of the choices is the least‑squares regression line of ﬁnal‑exam scores on pre‑exam total scores in this course?
In Professor Krugman's economics course, the correlation between the students' total scores prior to the final examination and their final‑examination scores is ?=0.5.�=0.5. The pre‑exam totals for all students in the course have mean 280280 and standard deviation 40.40. The final‑exam scores have mean 7575 and standard deviation 8.8. Professor Krugman has lost Julie's ﬁnal exam but knows that her total before the exam was 300.300. He decides to predict her ﬁnal‑exam score from her pre‑exam total. © Macmillan Learning (a) What is the slope of the least-squares regression line of final-exam scores on pre-exam total scores in this course? Give your answer to one decimal place. slope: What is the intercept? Give your answer as a whole number. intercept:
6. A comparison of life expectancy in random samples of 40 less-developed countries and 31 industrialized countries reveals the following (fictional) data. The standard deviations are significantly different from one another. Is there a significant difference in mean life expectancy between countries with these two levels of economic development? X=life expectancy of the resident at birth. Less-Developed Countries Mean=66.1 years N=40 Standard error of the difference between means=.60 Industrialized Countries Mean=76.7 years N=31
Suppose that you are designing an instrument panel for a large industrial machine. The machine requires the person using it to reach 2 feet from a particular position. The reach from this position for adult women is known to have a mean of 2.7 feet with a standard deviation of 0.5. The reach for adult men is known to have a mean of 3.1 feet with a standard deviation of 0.7. Both women's and men's reach from this position is normally distributed. If this design is implemented, (a) what percentage of women will not be able to work on this instrument panel? (b) What percentage of men will not be able to work on this instrument panel? (c) Explain your answers to a person who has never had a course in statistics. Click here to view page 1 of the table. Click here to view page 2 of the table. Click here to view page 3 of the table. Click here to view page 4 of the table.
times for a surgical procedure are normally distributed. there are two methods. method a has a mean of 29 minutes and a standard deviation of 5 minutes, while method b has a mean of 33 minutes and a standard deviation of 25 minutes. which procedure is preferred if the procedure must be completed within 37 minutes. method a, b, or either method