In a stream of vehicles, 20% of the vehicles travel at a constant 50 km/hr, 30% at a constant speed of 80 km/hr and the remaining vehicles travel at a constant speed of 100 km/hr. An observer travelling at a constant speed of 60 km/hr over a length of 6 km with the stream is passed by 10 more vehicles than he passes. When the observer travels against the stream at the same speed and over the same length of highway, the number of vehicles met is 390. What is the mean speed and flow of traffic stream being observed? How many vehicles travelling at 100 km/hr are met by the observer while he travels against the stream?

In a stream of vehicles, 20% of the vehicles travel at a constant 50 km/hr, 30% at a constant speed of 80 km/hr and the remaining vehicles travel at a constant speed of 100 km/hr. An observer travelling at a constant speed of 60 km/hr over a length of 6 km with the stream is passed by 10 more vehicles than he passes. When the observer travels against the stream at the same speed and over the same length of highway, the number of vehicles met is 390. What is the mean speed and flow of traffic stream being observed? How many vehicles travelling at 100 km/hr are met by the observer while he travels against the stream?

Traffic and Highway Engineering

5th Edition

ISBN:9781305156241

Author:Garber, Nicholas J.

Publisher:Garber, Nicholas J.

Chapter3: Characteristics Of The Driver, The Pedestrian, The Bicyclist, The Vehicle, and The Road

Section: Chapter Questions

Problem 10P

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