The distance between cities A and B is 120 miles. A car travels from A

Question

The distance between cities A and B is 120 miles. A car travels from A to B at 60 miles per hour and returns from B to A along the same route at 40 miles per hour. What is the average speed for the round trip?

(A) 48
(B) 50
(C) 52
(D) 56
(E) 58

(A) 48
(B) 50
(C) 52
(D) 56
(E) 58

sashiim20 · Answer

Total Distance  = 120 + 120 = 240  miles

Time taken to travel from A to B = Distance / speed  = \frac{120}{60} = 2  hours

Time taken to travel from B to A = Distance / speed  = \frac{120}{40} = 3  hours

Total Time Taken  = 2 + 3 = 5  hours

Average Speed = Total Distance Traveled / Total Time Taken

Average Speed  = \frac{240}{5} = 48  miles / hr . Answer (A)...

Luckisnoexcuse · Answer

From A to B Car took 2 hrs
From B to A Car took 3 hrs

D = 240, t = 5 S = 240/5 = 48 km/h

Second approach could be

(60*2 + 40*3)/(2+3) = 48

pushpitkc · Answer

Given:  
a(speed of travel from A to B) : 60 miles/hour
b(speed of travel from B to A) : 40 miles/hour
 
Average speed =  \frac{(2*a*b)}{(a+b)}

Substituting values,
Average speed =  \frac{(2*40*60)}{(40+60)}  
=  \frac{(2*40*60)}{(100)} = 2*4*6 = 48 (Option A)
 
P.S this is the formula for average speed, when the distance traveled across both 
the legs is the same.

BrentGMATPrepNow · Answer

Average speed = ( TOTAL distance )/( TOTAL travel time )

TOTAL distance = 120 + 120 =   240 miles

A car travels from A to B at 60 miles per hour....  
time = distance/speed
So, time = 120/60 =  2 hours

...and returns from B to A along the same route at 40 miles per hour  
time = distance/speed
So, time = 120/40 =  3 hours

TOTAL travel time =  2 hours  +  3 hours  =   5  hours

Average speed = (  240  )/(  5  )
= 48 miles per hour

Answer:  A

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Abhishek009 · Answer

Breakdown and solve -
 
Time required for onward journey = 2 hour
 
Time required for onward journey = 3 hour

Total distance is 240 miles
Total Time is 5 Hours

So, Average speed is 48 miles/hr , answer will be (A)

shashankism · Answer

Distance between A and B = 120 miles. 
1st : Car travels from A to B at 60 miles/hour. Time of travel = 120/60 = 2 hour.
2nd : Car travels from B to A at 40 miles/hour. Time of travel = 120/40 = 3 hour

Average speed of round trip = (120+120)/(2+3) = 48 miles per hour.

Answer A.

Nunuboy1994 · Answer

Easy. This is obviously a round trip question so we just apply some basic formulas

Total Distance= AvgSpeed * Total Time

120/60 =2
120/40 =3

240 = Avgspeed * 5
Avgspeed= 240/5

48

A

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The distance between cities A and B is 120 miles. A car travels from A

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The distance between cities A and B is 120 miles. A car travels from A

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