The municipality that controls that arterial road reduced the posted speed limit, hoping to reduce the average speed of the road to 60 km/h. After introducing the new speed limit, the municipality collected a new speed sample (sample size = 220) to calculate the operating speed. The average speed and the standard deviation of the new sample were found to be 61.09 km/h and 8.95 km/h, respectively. Based on this information, answer the following question a) Is the speed reduction (if there is any) statistically significant? b) Was the target speed achieved by introducing the new speed limit?

The municipality that controls that arterial road reduced the posted speed limit, hoping to reduce the average speed of the road to 60 km/h. After introducing the new speed limit, the municipality collected a new speed sample (sample size = 220) to calculate the operating speed. The average speed and the standard deviation of the new sample were found to be 61.09 km/h and 8.95 km/h, respectively. Based on this information, answer the following question a) Is the speed reduction (if there is any) statistically significant? b) Was the target speed achieved by introducing the new speed limit?

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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