I flew my tiny seaplane to visit my mother. On the flight up, I flew at 110 mph. On the way home, I flew 72 mph. What was my average speed for the trip?  Choose the correct choice from the following answers
A) 198 mph	B) 91 mph	C) 88 mph	D) 100 mph	E) 99 mph

Rationale: "( 110 mph + 72 mph ) / 2 = 91 mph correct answer is : b"
Answer: B