a tortoise walks north at 0.4 mg for 14 meters, then north at 0.2mg for 30 meters ,then south at 0.3 m/s for 60 meters.what is his average speed?

1 answer

Assuming you mean m/s not mg.

North at 0.4 m/s for 14 m takes 35 s.
North at 0.2 m/s for 30 m takes 150 s.
South at 0.3 m/s for 60 m takes 200 s.

Speed is independent on direction.

Average speed is:
= (total distance)/(total time)