Question 383994
A   to B = 60 mph
B   to A = 40 mph
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lets be practical
while going to B
speed = 40 mph
Assume it takes 1 hour
so distance = 40 miles
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while returning the speed = 60 mph
distance = 40
time= 40/60 = 2/3 hours
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Average speed for the trip = total distance / total time
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Total distance = 80 miles
total time= 1+2/3 hours
=1 2/3
=5/3 hours
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80/(5/3)
80*3/5
=16*3
=48 mph is the average speed
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does your teacher approve of this logic
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m.ananth@hotmail.ca