A fork truck can travel at 2 mph when loaded and 4 mph when

A fork truck can travel at 2 mph when loaded, and 4 mph when empty. What is its average speed?

Suppose one sided distance is 100x miles -> so time taken while loaded = 100x miles/2 miles per hour = 50x hours

when empty time taken = 100x miles / 4 miles per hour = 25x hours

Averge speed = distance travelled / time taken = 200x miles / 50x+25x hours = 200/75 mph=2.66 mph