“Half an hour after car A started traveling from Newtown to Oldtown, a distance of 62 miles, car B started traveling along the same road from Oldtown to Newtown. The cars met each other on the road 15 minutes after car B started its trip. If car A traveled at a constant rate that was 8 miles per hour greater than car B’s constant rate, how many miles had car B driven when they met?
(A)14
(B)12
©10
(D)9
(E)8”
Are these types of questions asked in gre? they are pretty time consuming
i can’t be sure but i don’t think so, it seems more like a GMAT question. btw is the answer A?
I would recommend that you try to skip the question and upon returning to it, try backsolving the question rather than doing the algebra for it. This may seem tedious, but it’s quite an efficient way to approach the problem when you are struggling for time. Start with option B, based on your result either repeat the process by using option D or select A.
In this example, let’s take B (12 miles), now try to find the speed for car B, subsequently finding out the speed of car A. Now that you know that car A has already traveled for 45 minutes, calculate the distance covered by car A. If the two distances don’t add up to 62, then B is wrong. If the distances are bigger than 62 then repeat with D (i.e. the smaller distance value) else choose A.
yes
Hi can you please confirm the answer is it 14 by any chance.
Set it up like this,
The distance is 62 miles. When these cars meet, both of their distances combined will equal 62 miles. Therefore:
62=Aspeed*Atime + Bspeed*Btime.
The speed is given in miles per hour. The time is given in minutes; so, you will have to convert. Car A has been driving for 30 minutes plus 15 minutes so 45 minutes total. Car B has been driving for 15 minutes. Divide both by 60 and that will give the time in hours.
62=Aspeed* \frac{45}{60} + Bspeed*\frac{15}{60}
Now, the speed: Aspeed is given as being 8mph more than Bspeed. Let’s call Bspeed b and Aspeed b+8. Finally this gives a solvable equation of
62=(b+8)* \frac{45}{60} + b*\frac{15}{60}
Solving for this gives b as 56mph. BUT don’t forget that the question has asked how many miles HAS car B gone. that is easy as distance = speed*time.
That will be 14