A sample of 100 over-all travel speed was observed on a four-lane, undivided Arterial Street. The sample mean was 35.45 mph, and the standard deviation of the sample was 5.20 mph. Assume that the sample of travel speeds was taken from a normal population. a) Find the percentage of vehicles in the population traveling between 33 and 44 mph. b) Between what limits may the mean of the population be expected to fall for a 95 percent level of confidence?

A sample of 100 over-all travel speed was observed on a four-lane, undivided Arterial Street. The sample mean was 35.45 mph, and the standard deviation of the sample was 5.20 mph. Assume that the sample of travel speeds was taken from a normal population. a) Find the percentage of vehicles in the population traveling between 33 and 44 mph. b) Between what limits may the mean of the population be expected to fall for a 95 percent level of confidence?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter4: Traffic Engineering Studies

Section: Chapter Questions

Problem 8P

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