Average Speeds

The Problem:

 On a journey through towns and country, a driver averages a speed of 18 mph for the 7 miles of town driving, and 36 mph for the 14 miles of country driving.

What is her average speed for the complete journey ?

(Harder)

 On a faster stretch of road, the motorist averages 80 km/hr for 12 km, then 120 km/hr for 12 km. What is her overall average speed for this stretch ?

 

Open the File as a Word Document

 

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Last modified: June 18, 2007