Elena left Riverton and drove to Lakehurst, which is 420

Question

Elena left Riverton and drove to Lakehurst, which is 420 kilometers away. At the same time, Marta left Lakehurst and drove along the same route to Riverton. If neither driver ever exceeded the speed limit of 80 kilometers per hour, did Marta reach Riverton before Elena reached Lakehurst?

(1) After 4 hours of driving, they passed each other at a point 140 kilometers from Riverton.

(2) Marta’s average (arithmetic mean) speed for the entire trip was 70 kilometers per hour.

Bunuel · Answer

Data Sufficiency Butler: May 2025 
 
  May 6 
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Xdsa · Answer

answer is option A

statement 1: after 4 hrs of driving elena travelled 140 KM and marta travelled 280 KM so the speed of elena is 35 KMph whereas for marta it's 70 KMph so based on the speed marta reaches before elena hence statement 1 is sufficient

statement 2: average speed of marta is alone provided which is not sufficient

SS990 · Answer

Answer i think is C
Speed is always less than 80 for both.

1) says in 4hrs they met at 140km from R. 
But we do not know any info about rest of the journey where MArtha has to cover 140km and Elena 280km....so not sufficient
Lets say for the sake of this problem, Martha travels rest of the journey at 140km at 1km/hr and ELena at 80km/hr, since it only says they dont exceed 80km/hr speed, then Martha will have taken 4+140hrs to reach R and Elena 4+3.5hrs to reach L

2) Martha travels at constant 70km/hr then total journey would take 6hrs in total. But we know nothing about Elena's so not sufficient to answer the Question

combining we know Elena has to cover 280km left in 2hrs hrs to match this which is speed of 140km/hr for her which as per Q statement cant happen. Hence MArthe reaches sooner, hence C

Adit_ · Answer

Statement 1:
We know the distances travelled thus far but we have no info about the speeds of remaining distances for each of them.
INSUFFICIENT.

Statement 2:
We only have the average speed of one of them here.
INSUFFICIENT.

Combining the two:
We see that Marta ended up taking 6 hrs.
We aren't sure when exactly they met each other.
But even considering the critical point of 4 hrs:
Marta travels 140km in 2 hrs more.
For Elena to reach earlier he would have to travel 280km in 2 hrs but speed limit is only 80.
So Marta always reaches earlier.

If they met each other after 5 hrs its even worse as Elena would have to travel 280km in 1 hr which is even more outlandish!
Thus Marta reaches earlier.
SUFFICIENT.

Answer:  Option C

BongBideshini · Answer

Statement (1)

In the same 4 hours:
 
 Marta covered 280 km  
 Elena covered 140 km   
So Marta is traveling faster (in fact, twice as fast).
Since both are travelling the same total distance of 420 km, the faster driver will definitely finish first.

Statement (1) alone is sufficient.

Statement (2) 
Marta’s average speed for the entire trip was 70 km/h.
But Elena can have more than 70km/h speed or less than 70km/h speed
So, we can not determine who is faster
 Not sufficient

Ans (A)

Elena left Riverton and drove to Lakehurst, which is 420

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GMAT Data Sufficiency (DS) Questions

Elena left Riverton and drove to Lakehurst, which is 420

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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My Rewards