Concept:  The question tests on TSD


Average speed over 2 equal distances travelled at speeds a and b is = 2aba+b2aba+b

If we get the speeds, we can find the average speed.

Statement 1: Morris drove from A to B at 40 miles per hour and returned back at 60 miles per hour.

We have the speeds over the 2 distances. We can find the average speed by the equation above.

Therefore Statement 1 Alone is Insufficient. Answer options could be A or D.

Statement 2:The distance between the towns A and B was 120 miles.

With this we cannot find the average speed.

Therefore Statement 2 Alone is Insufficient.

Option A