STATS WK IV HOMEWORK

.docx

School

Garden City Community College *

*We aren’t endorsed by this school

Course

302

Subject

Statistics

Date

Jan 9, 2024

Type

docx

Pages

4

Uploaded by nvrduplic8

Report
Question 1 0 / 1 point Find P(Z ≤ 3). Round answer to 4 decimal places. Answer: ___.0013 ___ (0.9987, .9987) Hide question 1 feedback In Excel, =NORM.S.DIST(3,TRUE) Question 2 1 / 1 point Find P(-1.96 ≤ Z ≤ 1.96). Round answer to 2 decimal places. Answer: ___.95 ___ Hide question 2 feedback In Excel, =NORM.S.DIST(1.96,TRUE)-NORM.S.DIST(-1.96,TRUE) Question 3 1 / 1 point Find P(1.31 < Z < 2.15). Round answer to 4 decimal places. Answer: ___.0793 ___ Hide question 3 feedback In Excel, =NORM.S.DIST(2.15,TRUE)-NORM.S.DIST(1.31,TRUE) Question 4 1 / 1 point Which type of distribution does the graph illustrate? Uniform Distribution Poisson Distribution Normal Distribution Right skewed Distribution Question 5 The cost of unleaded gasoline in the Bay Area once followed a normal distribution with a mean of $4.59 and a standard deviation of $0.10. Sixteen gas stations
from the Bay area are randomly chosen. We are interested in the average cost of gasoline for the 16 gas stations. What is the approximate probability that the average price for 16 gas stations is over $4.69? 0.1587 Almost zero Unknown 0.0943 Hide question 5 feedback New SD = .10/SQRT(16) = .025 P(x > 4.69) = 1 - P(x < 4.69) In Excel, =1-NORM.DIST(4.69,4.59,.025,TRUE) You might get an answer with an "E" in it. The "E"; means scientific notation. 3.16712E-05 decimal answer is, .0000316712 Question 6 1 / 1 point The average lifetime of a set of tires is three years. The manufacturer will replace any set of tires failing within two years of the date of purchase. The lifetime of these tires is known to follow an exponential distribution. What is the probability that the tires will fail within two years of the date of purchase? 0.8647 0.2212 0.4866 0.9997 Hide question 6 feedback P(x < 2) In Excel, =EXPON.DIST(2,1/3,TRUE) Question 7 1 / 1 point The commute time for people in a city has an exponential distribution with an average of 0.5 hours. What is the probability that a randomly selected person in this city will have a commute time between 0.4 and 1 hours? Answer: (round to 3 decimal places) ___.314 ___ Hide question 7 feedback P(.4 < x < 1) P(x < 1) - P(x < .4) In Excel, =EXPON.DIST(1,1/0.5,TRUE)-EXPON.DIST(0.4,1/0.5,TRUE) Question 8 1 / 1 point The life of an electric component has an exponential distribution with a mean of 8 years. What is the probability that a randomly selected one such component has a life less than 5 years? Answer: (round to 4 decimal places) ___.4647 ___ Hide question 8 feedback P(x < 5) In Excel, =EXPON.DIST(5,1/8,TRUE) Question 9 1 / 1 point The average lifetime of a certain new cell phone is three years. The manufacturer will replace any cell phone failing within two years of the date of purchase. The lifetime of these cell phones is known to follow an exponential distribution. What is the median lifetime of these phones (in years)? 5.5452 1.3863 0.1941 2.0794 Hide question 9 feedback Median Lifetime is the 50th percentile. Use .50 in the equation and the rate of decay is 1/3 Question 10 1 / 1 point The waiting time for a table at a busy restaurant has a uniform distribution between 0 and 10 minutes. What is the 95th percentile of this distribution? (Recall: The 95th percentile divides the distribution into 2 parts so that 95% of area is to the left of 95th percentile) _______ minutes Answer: (Round answer to one decimal place.)
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
  • Access to all documents
  • Unlimited textbook solutions
  • 24/7 expert homework help