A bus goes A to B with 45km /h and return B to A with 85km/h , what is the average speed

A bus goes A to B with 45km /h and return B to A with 85km/h , what is

1.	A bus goes A to B with 45km /h and return B to A with 85km/h , what is the average speed
Answer» A bus goes A to B with 45km /h and return B to A with 85km/h , what is the average speed