+1-415-670-9189
info@expertsmind.com
Confidence interval estimate for variance of life expectancy
Course:- Basic Statistics
Reference No.:- EM1317098




Assignment Help
Assignment Help >> Basic Statistics

Q1) A sample of 23 European countries found that variance of life expectancy was 7.3 years. Determine the 95% confidence interval estimate for variance of life expectancy in Europe?

a) 27.2 < σσ2 < 118.3

b) 5.6 < σ2 < 10.3

c) 4.4 < σ2 < 14.6

d) 28.9 < σ2 < 115.0

Q2) Determine the 95% confidence interval for standard deviation of lengths of pipes if sample of 26 pipes has standard deviation of 10 inches.

a) 14.0 < σ < 16.0

b) 7.8 < σ < 13.8

c) 74.0 < σ < 126.0

d) 60.8 < σ < 190.5

Q3)  Average gas mileage of certain model car is 26 miles per gallon.  If gas mileages are normally distributed with standard deviation of 1.3, determine the probability that randomly selected car of this model has gas mileage between 25.8 and 26.3 miles per gallon.

a)   0.15

b)  0.85

c)  0.70

d)  0.30

Q4) At large department store, average number of years of employment for cashier is 5.7 with standard deviation of 1.8 years. If number of years of employment at this department store is normally distributed, determine the probability that cashier chosen at random has worked at the store for over 10 years?

a) 0.4916

b) 0.9916

c) 0.0084

d) 0.0054

Q5)  To be accepted into top university, applicants should score within top 5% on the SAT exam.  Given that SAT test scores are normally distributed with mean of 1000 and standard deviation of 200, compute the lowest possible score a student needs to qualify for acceptance into the university?

a) 1330

b) 1400

c) 1250

d) 1100




Ask Question & Get Answers from Experts
Browse some more (Basic Statistics) Materials
Superior Medical System's 2005 balance sheet showed total common equity of $2,050,000. The company had 100,000 shares of stock outstanding which sold at a price of $57.25 pe
(A) What sums are needed to calculate a correlation coefficient? (B) What are the two ways of testing a correlation coefficient for significance?
Let Sn denote the total of the outcomes through the nth toss. Show that there is a limiting value for the proportion of the first n values of Sn that are divisible by 7, and c
Based on this, compute a 99% confidence interval for the proportion of all letters mailed in the United States that were delivered the day after they were mailed.
Calculate the interval μ ± 2σ. What is the probability that X will fall into this interval? d. If you were to select a very large number of values of X from the population,
Given this information, and assuming a normally distributed population of weights, would you feel very secure in advising management that the machine should be shut down? Us
Is sample of 25 papers large adequate to give a good estimate of mean score of all 42,000 students on this exam problem? Explain your answer.
Suppose that an IQ test was given to a large group of persons, the scores are assumed to be from a normally distributed population, that mean = 100 and s (standard deviation