GRE Exam Numerical Ability Time Distance and Speed

Two cars started from the same point and traveled on a straight course in opposite directions for exactly 2 hours, at which time they were 208 miles apart. If one car traveled, on average, 8 miles per hour faster than the other car, what was the average speed for each car for the 2-hour trip?

Read Solution (Total 2)

48 mph and 56 mph

If x is speed of one car, then

2(x+x+8)= 208

x= 48 mph
15 years agoHelpfull: Yes(6) No(0)

Let the speed of 1 car = x mph, distance covered = y miles
speed of 2nd car = x+ 8 mph, distance covered= 208-y miles
time= distance/ speed= 2hrs
for car1, y/x=2 , y=2x
for car2, 208-y/x+8 = 2 (put y=2x)
208-2x = 2x+ 16, on solving x =48

speed of car1= 48mph and of car2 = 56mph
15 years agoHelpfull: Yes(5) No(0)

GRE Other Question

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