how is the answer D?

Car A moves towards Car B for 12 hours at a speed of 40 miles per hour, and then Car B starts moving towards Car A at a speed of 80 miles per hour.

Now, \(A\) completes \(480\) miles and then car \(B\) starts. What if car \(B\) is at \(80\)km distance when it started? Then the distance will be less.

We do not have all the details needed.

Answer D

What rx10 suggests is intuitive. RTD problems of meeting involve a time factor. Here rates, time parameters and distances are related among themselves. Even if it's clear what the rates are considered, time shifts do not help solving for two distances. Hence, answer is D.

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Car A moves for 12 hours


Let us say time they meet is x


A will move 12 + x hours before they meet


Car B will move for x hours


Quantity A

Distance moved by car A


40 ( 12 + x )

480 + 40x


Quantity B

Distance moved by car B

80x

subtract 40x from both

A = 480

B = 40x


So answer is D

Adewale Fasipe, GRE/GMAT quant instructor from Nigeria
https://www.teacheron.com/tutor-profile/8tG7?r=8tG7

To establish the correlation between the overall distances covered by Car A and Car B, it is essential to assess the distances individually covered by each car. However, due to the absence of the value of t, the exact distance covered by Car B remains unknown. The inability to ascertain the value of t prevents a direct comparison of the distances traveled by both cars. Consequently, the connection between the two quantities cannot be deduced based on the provided information.