PSAT Math Multiple-Choice Question 50: Answer and Explanation

Question: 50

A survey company gathered data regarding people's transportation habits in four major U.S. cities. The survey asked participants in each of these cities to indicate whether they regularly used a personal vehicle, public transportation, or neither to commute. Participants were not limited to one response and could check both personal vehicle and public transportation. The results are shown below.

Which one of the following statements is supported by the data shown above?

• A. Approximately 20% more people checked both personal vehicle and public transportation in Boston than in New York.
• B. Washington, D.C. has the highest proportion of people that regularly use both public transportation and a personal vehicle.
• C. The number of people that reported regularly using public transportation in New York is approximately 230% more than the number that reported regularly using a personal vehicle.
• D. The ratio of personal vehicle use to public transportation use was lowest in San Francisco.

Correct Answer: A

Explanation:

A

The question asks for a statement supported by the data in a table. Read each answer carefully and use Process of Elimination. To determine how many people used both forms of transportation in Boston and New York, use the Group Equation: Total = Group 1 + Group 2 + Neither - Both. For Boston, this becomes 7,556 = 5,281 + 3,504 + 1,025 - B. Combine like terms: 7,556 = 9,810 - B. Subtract 9,810 from both sides: -2,254 = -B. Divide both sides by -1 to find that 2,254 people use both forms of transportation in Boston. Repeat the same process for New York: 7,789 = 2,476 + 5,738 + 1,459 - B becomes 7,789 = 9,673 - B, and -1,884 = -B, so 1,884 people in New York use both forms of public transportation. Finally, determine whether 20% more people used both forms of transportation in Boston by using the percent change equation: . This equation becomes . This is approximately 20%, so the statement in (A) is supported by the data. The correct answer is (A).