Official Explanation:
This is a tough question that not only deals with numbers vs. percents but also throws in downtown vs. the overall city, of which downtown is a part. The argument is as follows: There are more sports cars per mile in downtown T. than in downtown G. If the entire city is compared, however, the number of cars per square mile is greater in G.
(D) is correct because we know that T., per square mile, has more cars in downtown than G. but G. has more cars, per square mile, overall. Since the city is only made up of downtown, exurbs ,and suburbs, there must be more cars per square mile in the exurbs and suburbs of G. than in those of T.
(A) is tempting since we are led to believe that there are more total cars in G. than in T. Read carefully, though. More cars per square mile does not equal more total cars. In other words, it’s a question of density of sports cars in an area, not the total number of cars in that area. If metropolitan T. is much larger than metropolitan G., then it will have more total cars.
(B) is incorrect for the same reason as (A).
(C) is wrong because we only know about car per square mile (see (A)). We don’t know about total area.
(E) is wrong because the paragraph gives us nothing regarding the breakdown between the downtown vs. the non-downtown areas.
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