Cigarette Smoking A researcher found that a cigarette smoker smokes on average 30 cigarettes a day. She feels that this average is too low. She selected a random sample of 9 smokers and found that the mean number of cigarettes they smoked per day was 32. The sample standard deviation was 2.4. At a = 0.10, is there enough evidence to support her claim? Assume that the population is approximately normally distributed. Use the critical value method and tables. Part 1 of 5 (a) State the hypotheses and identify the claim. H:u = 30 not claim H :µ > 30 | claim This hypothesis test is a one-tailed v test. Part: 1/ 5 Part 2 of 5 (b) Find the critical value(s). Round the answer to three decimal places. If there is more than one critical value, seperate them with commas. Critical value(s):

Cigarette Smoking A researcher found that a cigarette smoker smokes on average 30 cigarettes a day. She feels that this average is too low. She selected a random sample of 9 smokers and found that the mean number of cigarettes they smoked per day was 32. The sample standard deviation was 2.4. At a = 0.10, is there enough evidence to support her claim? Assume that the population is approximately normally distributed. Use the critical value method and tables. Part 1 of 5 (a) State the hypotheses and identify the claim. H:u = 30 not claim H :µ > 30 | claim This hypothesis test is a one-tailed v test. Part: 1/ 5 Part 2 of 5 (b) Find the critical value(s). Round the answer to three decimal places. If there is more than one critical value, seperate them with commas. Critical value(s):

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Description: Cigarette Smoking A researcher found that a cigarette smoker smokes on average 30 cigarettes a day. She feels that thisaverage is too low. She selected a random sample of 9 smokers and found that the mean number of cigarettes they smoked perday was

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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Suppose you buy a new car whose advertised mileage is 20 miles per gallon (mpg). After driving your car for several months, you find that its mileage is 16.5 mpg. You telephone the manufacturer and learn that the standard deviation of gas mileages for all cars of the model you bought is 1.02 mpg. a. Find the z-score for the gas mileage of your car, assuming the advertised claim is correct. b. Does it appear that your car is getting unusually low gas mileage? Question content area bottom Part 1 a. z=enter your response here (Round to two decimal places as needed.)
Times for a surgical procedure are normally distributed. There are two methods. Method A has a mean of 31 minutes and a standard deviation of 2 minutes, while method B has a mean of 35 minutes and a standard deviation of 1.0 minutes. (a) Which procedure is preferred if the procedure must be completed within 30 minutes? O Method A O Method B O Either Method (b) Which procedure is preferred if the procedure must be completed within 38.0 minutes? O Either Method O Method A O Method B (c) Which procedure is preferred if the procedure must be completed within 37 minutes? O Method B O Either Method O Method A < Prev 19 of 19 Next to search 22 立
In a large section of a statistics class, the points for the final exam are normally distributed, with a mean of 74 and a standard deviation of 8. Grades are assigned such that the top 10% receive A's, the next 20% received B's, the middle 40% receive C's, the next 20% receive D's, and the bottom 10% receive F's. Find the lowest score on the final exam that would qualify a student for an A, a B, a C, and a D. The lowest score that would qualify a student for an A is nothing. (Round up to the nearest integer as needed.) The lowest score that would qualify a student for a B is nothing. (Round up to the nearest integer as needed.) The lowest score that would qualify a student for a C is nothing. (Round up to the nearest integer as needed.) The lowest score that would qualify a student for a D is nothing. (Round up to the nearest integer as needed.)
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