Question 2: A student safety advocacy group believes that drivers are speeding down Manhattan College Blvd. To prove their point, they wish to college vehicle speed data. Previous research has shown that the standard deviation of vehicle speeds on this functional class of roads is 7.00 mph. A. How many vehicles will the group need to sample to determine the 50 percentile speed if they wish to be 95 5% confident in their results plus or minus 3.00 mph? B. How does the 50" percentile required sample size change if we are concerned about the 85" percentile? C. How does the 50" percentile required sample change if we want the results to be accurate to plus or minus 1.5 mph?

Question 2: A student safety advocacy group believes that drivers are speeding down Manhattan College Blvd. To prove their point, they wish to college vehicle speed data. Previous research has shown that the standard deviation of vehicle speeds on this functional class of roads is 7.00 mph. A. How many vehicles will the group need to sample to determine the 50 percentile speed if they wish to be 95 5% confident in their results plus or minus 3.00 mph? B. How does the 50" percentile required sample size change if we are concerned about the 85" percentile? C. How does the 50" percentile required sample change if we want the results to be accurate to plus or minus 1.5 mph?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter4: Traffic Engineering Studies

Section: Chapter Questions

Problem 3P

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