# 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.

Correct!

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)   $\mathrm{ speed = \frac{d}{\Delta t}}$