The rate at which a road wears depends on various factors, including

Answer is easy peasy D
Explanation :-
Road get bad due to climate, amount of heavy traffic, size of the vehicle, and "WEIGHT OF THE VEHICLE."
A single wide road that has been divided into two parallel narrow roads - has become bad on one side but is good at the other side. WHY?

Now it cannot be weather because weather will affect the entire road. Both sides of the road should have gone bad.
It can't be the traffic because question stem tell us both side carry the same amount of traffic
It can't be the size of the vehicle because question stem tells us that the vehicles on both sides are trucks.

What is remaining then :- the weight of the trucks.
The question stem tells us that trucks go to the sea port. May be the trucks carry heavy cargo on one side, dump it and then come back empty or wth a lesser weight.
THIS IS THE ONLY LOGICAL EXPLANATION.

LETS MATCH IT WITH AN ANSWER CHOICE.
D) A greater tonnage of goods is exported from Rittland’s seaport than is imported through it.

CORRECT:- The truck carry goods from city to the seaport---> The goods are then unloaded and exported---->Meanwhile the trucks are empty now---> Empty truck or trucks with small cargo retun back to the city-----> Now truck has lower weight-----> lower weight means lower damage to the roads.

CORRECT ANSWER IS D


The rate at which a road wears depends on various factors, including climate, amount of traffic, and the size and weight of the vehicles using it. The only land transportation to Rittland’s seaport is via a divided highway, one side carrying traffic to the seaport and one carrying traffic away from it. The side leading to the seaport has worn faster, even though each side has carried virtually the same amount of traffic, consisting mainly of large trucks.

Which of the following, if true, most helps to explain the difference in the rate of wear?

A. The volume of traffic to and from Rittland’s seaport has increased beyond the intended capacity of the highway that serves it.
B. Wear on the highway that serves Rittland’s seaport is considerably greater during the cold winter months.
C. Wear on the side of the highway that leads to Rittland’s seaport has encouraged people to take buses to the seaport rather than driving there in their own automobiles.
D. A greater tonnage of goods is exported from Rittland’s seaport than is imported through it.
E. All of Rittland’s automobiles are imported by ship.

Type- Explain
Boil it down - The side leading to the seaport has worn faster, even though each side has carried virtually the same amount of traffic, consisting mainly of large trucks.
Pre- thinking - Climate and amount of traffic is same . But the weight of vehicles might differ

D. A greater tonnage of goods is exported from Rittland’s seaport than is imported through it. - Correct answer

Argument Construction
Situation The side of a divided highway leading to a seaport has worn faster than the side leading away from the seaport. Both sides carry roughly the same amount of traffic, mainly
consisting of large trucks.

Reasoning What could explain why the side of the highway leading to the seaport has worn faster than the other side?
We are told that climate, amount of traffic, and the size and weight of vehicles on a road affect how quickly the road wears. We are also told that the amounts of traffic on the two sides of the highway are almost identical. Probably the climate on the two sides is also almost identical. Thus, the most likely explanation for the different rates of wear is that the size or weight of the vehicles driving on the two sides differs significantly. So any factor that would make the vehicles' size or weight greater on the side leading to the seaport than on the other side could help explain the difference in wearing.

A The increased traffic volume affects both sides of the highway, so it does not help explain why one side is wearing faster than the other.

B The winter weather affects both sides of the highway, so it does not help explain why one side is wearing faster than the other.

C The buses may contribute to wear on the side of the highway leading to the seaport, but not necessarily more than the car traffic they are replacing would (though the increased use of buses instead of cars may decrease the amount of traffic, buses would be heavier than cars and thus may result in an equal or greater amount of wear). Furthermore, the buses have to come back on the other side, probably carrying the returning travelers who have not left their cars at the airport.

D Correct. This suggests that the many trucks visiting the seaport tend to be more heavily laden with goods when traveling on the side of the highway leading to the seaport than when returning on the other side. The resulting difference in the trucks' weight when traveling on the two sides could explain the different rates of wear.

E These automobiles would be transported along the side of the highway leading from the seaport, but not along the side leading to it. This would likely create a pattern of wear opposite to the one observed.

The correct answer is D

"D. A greater tonnage of goods is exported from Rittland???s seaport than is imported through it."

Does anyone realize that an export is going out of the island and imports is coming into it? If greater tonnage is exported through from Rittland than heavier weight is on the leaving side of the highway not the coming in. Therefore the GMAT has the wrong answer.

I believe the GMAT is trying to say more stuff from the shipping yard is being exported than imported so trucks ride up to the ol' shipping yard with exports and ride out with imports but this reading isn't logical. There is no mention that we are only measuring goods that are shipped and this is what counts as exports.

A lot of what you're saying here seems right, but the GMAT definitely didn't make a mistake. Taking some of your statements out of order:



Agreed -- and this is the "side leading to the seaport", which has "worn faster", according to the question.



Yup, I agree with this, too. That's exactly what they're trying to say: the trucks are loaded when they head to the seaport, but emptier on the way back. Why might this be the case? Lots of exports heading out at Rittland's seaport, but fewer exports coming back in.



And I'm not sure how you decided that this is illogical. Here's what I think the issue might be: remember that the question asks for the answer choice that most helps to explain the difference in the rate of wear. It's not asking you for a 100% airtight, perfect answer: it's asking for the answer that offers the best explanation.

So sure, we could concoct stories that would make (D) a less-than-perfect answer. For example, maybe some goods reach the seaport and are consumed there -- so there isn't a perfect relationship between exports/imports and the goods that are transported along the only road to/from the seaport.

But don't let perfect be the enemy of the good: if "a greater tonnage of goods is exported through the seaport" than imported through it, it's not unreasonable to expect the trucks to wear the road down more on their way to the seaport than on their way back. And at the very least, (D) is a heck of a lot better than any of the alternatives.

I hope this helps!

I would hardly call my response "concocting." If we assume 2 scenarios.

1) if we assume it is a shipyard Rittland's Seaport could easily import more goods by ship then export the goods by truck to another country beside it. There's very little reason to assume if its by ship its an export and by truck is automatically an import.

2Similar to 1, there is nothing in the question that tells us that export go out by ship. You're the one who concocted that. In fact the word ship isn't even mentioned. It's very easy to assume only trucks exist and exports again go out by truck and imports in by truck. Therefore D is not logical.

D is Correct - Suggests that many trucks visiting the seaport tend to be more heavily laden with goods when traveling on the side of the highway leading to the seaport than when returning on the other side. The resulting difference in the trucks' weight when traveling on the two sides could explain the different rates of wear of roads.

3 factors mentioned for wear
1. Climate. Will be same for both roads
2. Amount of traffic. Mentioned to be same in passage
3. Size and Weight ..we have to look for answer which mentions weight

Hence D

If the road leading to sea port has worn faster, doesn't that mean weight of imports were more than weight of exports?

The rate at which a road wears depends on various factors, including climate, amount of traffic, and the size and weight of the vehicles using it. The only land transportation to Rittland’s seaport is via a divided highway, one side carrying traffic to the seaport and one carrying traffic away from it. The side leading to the seaport has worn faster, even though each side has carried virtually the same amount of traffic, consisting mainly of large trucks.

Which of the following, if true, most helps to explain the difference in the rate of wear?

(A) The volume of traffic to and from Rittland’s seaport has increased beyond the intended capacity of the highway that serves it.

(B) Wear on the highway that serves Rittland’s seaport is considerably greater during the cold winter months.

(C) Wear on the side of the highway that leads to Rittland’s seaport has encouraged people to take buses to the seaport rather than driving there in their own automobiles.

(D) A greater tonnage of goods is exported from Rittland’s seaport than is imported through it.(Correct)

(E) All of Rittland’s automobiles are imported by ship.

VeritasKarishma Ma'am, can you please explain why 'D' is correct?
The option says ' A greater tonnage of goods is exported from Rittland’s seaport than is imported through it.', which means the condition of the road leading to the seaport would be in a much better condition than the other road.

If a greater number of loaded trucks use the traffic to the seaport highway then the road will wear sooner than the other one. Option D says amount of export of the country is higher than import that means more loaded trucks use the traffic to the seaport highway than the traffic in the highway. So the answer is D.

Would Choice E be considered a weakener, if anything, because importing more cars coming in = heavier load on the side of the road carrying traffic away from the seaport to distribute the automobiles?

Thank you!

This doesn't give a difference between the two roads.

woohoo921

Careful, you don't want to think in terms of strengthening/weakening on a Discrepancy question. All the information we've been presented with is true, so there's nothing to strengthen or weaken. We are just trying to understand why this discrepancy exists.

Still, I know what you mean with E. If anything, you'd expect that bringing in a bunch of heavy automobiles would wear down the incoming side of the road. But even if this went the other way (lots of autos getting exported), it wouldn't by itself do anything to resolve the discrepancy. We need comparative information about the two sides. D gives us total tonnage, so it's easy to see why the outgoing side would get more wear. Just knowing that lots of cars are transported along one side wouldn't tell us why that side is more worn down than the other. For all we know, cars could be LIGHTER than whatever is traveling the other way: tanks, massive oil drums, blue whales, neutron stars . . . Okay, maybe not those, but you know what I mean, right? We need comparative info, and E doesn't give us that.

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