SOLUTION: A man drives from home to work at a speed of 50mi/h. The return trip from work to home is traveled at the more leisurely pace of 30 mi/h. What is the man's average speed for the ro

Question 249429: A man drives from home to work at a speed of 50mi/h. The return trip from work to home is traveled at the more leisurely pace of 30 mi/h. What is the man's average speed for the round trip?
(I know the answer is not 40mi/h though)
Answer by oberobic(2304) (Show Source): You can put this solution on YOUR website!
We know the basic formula for distance problems is: d = rt, where d=distance, r=rate, t=time.
We know the man drives to work at 50 mph.
We know he drives home at 30 mph.
We know the distance is the same both ways.
What we do not know are the times involved.
.
Let's assume he drives 30 miles to and from work.
At 50 mph it takes him 30/50 or .6 of an hour to drive to work. .6*60 = 36 minutes
At 30 mph it takes him 30/30 or 1 hr to drive home = 60 minutes
.
So the total elapsed time is 96 minutes to drive 60 miles.
96 minutes = 1.6 hr
.
Going back to d=rt
.
60 miles = r mph * 1.6 hr = 1.6r
.
Dividing both sides by 1.6
37.5 = r
r = 37.5
.
Checking our work...
How far will the car go in 1.6 hr at 37.5 mph?
60 miles
OK.
RELATED QUESTIONS
A man drives to work at 40mph. He drives home,along the same route, at 60mph. What is his (answered by Alan3354)

The Smiths traveled to Voyageurs National Park to view the spring foliage at its peak.... (answered by Alan3354)

Mr.E drives to work. because of traffic conditions he averages 40 mi/hr. he return home... (answered by richwmiller)

A man leaves his home and drives to the beach at an average speed of 50 mph and returns... (answered by mananth)

A man leaves his home and drives to the beach at an average speed of 50 mph and returns... (answered by richwmiller)

a man drove from his home to the airport at a distance of 40 miles and then returned home (answered by mananth)

Francisco drives to work, which is 23 miles away, at a speed of 40 miles per hour. He... (answered by josmiceli)

A man walks from his home to a town 6 km away at a speed of 4 km/h and returns home at a... (answered by Alan3354,ikleyn)

A man drives from his home at 30 miles per hour to the shopping center which is 20 miles... (answered by macston)