College Physics (7th Edition)

a). Displacement from starting point = $\sqrt (400^{2}+300^{2})=500 km.$ b). Average velocity = $\frac{500 km}{75 min}=\frac{500 km}{1.25 hr}=400 km/hr$ c). Average speed = $\frac{(400+300)km}{1.25hr}=560 km/hr$ d). Average speed is not same in magnitude as average velocity because distance and displacement are different.
a). Displacement from starting point = $\sqrt (400^{2}+300^{2})=500 km.$ b). Average velocity = $\frac{500 km}{75 min}=\frac{500 km}{1.25 hr}=400 km/hr$ c). Average speed = $\frac{(400+300)km}{1.25hr}=560 km/hr$ d). Average speed is not same in magnitude as average velocity because distance and displacement are different.