Answer to Question #288221 in Physics for Xee

Question

A goat and a dog are in a road race. The goat moves the entire 1000m at the speed of 0.2m/s. The dog runs the first 200m at 2m/s, stops to rest for 45minutes and then continues the race to finish the last 800m with an average speed of 3m/s.

Answer 1

The time it took for the goat to finish the race is 1000/0.2=5000 s.

The time it took for the dog:

$t_1=200/2=100\text{ s},\\ t_2=45·60=2700\text{ s},\\ t_3=800/3=267\text{ s}.\\ t_d=t_1+t_2+t_3=3067\text{ s}.$

The dog is the winner.