Hint for process of elimination: Whenever an SAT gives a question that is realistic, it attempts to make sure that the solution is realistic. Therefore, if you happen to know anything about New York City, use that.
Also, notice that the ratio of the population of NYC to the population of the rest of New York is $latex 8:11 $. That means that a bit less than half of all New Yorkers live in New York City. Therefore, you should expect the answer to be a little under $latex 50\% $. That leaves one or maybe two choices.
Read on for a full solution.
Answer: C
Solution: Since the ratio of the NYC population to the population of the rest of New York is $latex 8:11 $, the ratio of the NYC population to the population of all of New York is $latex 8:(11+8) = 8:19 $. Therefore the percentage of New Yorkers that live in NYC is $latex \dfrac{8}{19} \times 100\% \approx 42.1\% $.