SOLUTION: If a person travels 40 mph going to city A to B, and 60 mph returning from B to A, what is the average speed of the entire trip? Explain. I told my teacher that the average s

Question 384078: If a person travels 40 mph going to city A to B, and 60 mph returning from B to A, what is the average speed of the entire trip? Explain.

I told my teacher that the average speed was 50 mph and got marked wrong. Where did I go wrong?
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
lets be practical
while going to B
speed = 40 mph
Assume it takes 1 hour
so distance = 40 miles
..
while returning the speed = 60 mph
distance = 40
time= 40/60 = 2/3 hours
..
Average speed for the trip = total distance / total time
..
Total distance = 80 miles
total time= 1+2/3 hours
=1 2/3
=5/3 hours
..
80/(5/3)
80*3/5
=16*3
=48 mph is the average speed
..
does your teacher approve of this logic
..
m.ananth@hotmail.ca

RELATED QUESTIONS
Racer X travels from city Avalon to city Babylonia the speed of 60 mph. On the way back... (answered by oberobic)

Tahir travels from A to B at a speed of 40 mph, and returns along the same route a speed... (answered by bucky)

A person travels 136 miles from one town to a city at an average speed of 77 mph and then (answered by Alan3354)

you travel from city a to city b and back you maintain a speed of 60 mph the entire trip... (answered by ankor@dixie-net.com)

A car travels from A to B. First half of the distance it moves with a speed 60 mph, and... (answered by nerdybill)

A car drove from town A to town B at an average of 60 mph. On the return trip from town B (answered by Fombitz,ikleyn,solver91311)

A motorist traveled from city A to city B at an average speed of 50 mph. On the return... (answered by stanbon)

A train travels from city A to city B and then to city C. The distance from A to B is 175 (answered by Theo,josgarithmetic)

Joey drives from city A to city B at an average of 72 mph. Once he arrives at city B, he... (answered by josgarithmetic)