Problem 2-62 - Distance and speed - Part 2 (b)

A truck travels at \(80\; km/h\) for \(30\; min\), then at \(60 \;km/h\) for \(1.5\; hr.\) Assuming 2 significant digits in the given numbers, calculate the truck's

(a) total distance traveled, and
(b) average speed.



The distance traveled \(d\) in time \(\Delta t\) at a constant speed is given by:

(A)   \(\mathrm{speed = d \dot \; \Delta t}\)

(B)   \(\mathrm{speed = \frac{\Delta t}{d}}\)

(C)   \(\mathrm{ speed = \frac{d}{\Delta t}}\)