PSAT Math Grid-Ins Question 53: Answer and Explanation

Question: 53

Boeing Jets	Coach	Business	First Class
747-400	310	52	12
767-300	151	26	6
777-200	194	37	16
777-300	227	52	8

The table above shows the seating configuration for several commercial airplanes. The day before a particular flight departs, a travel agent books the last seat available for a client. If the seat is on one of the two Boeing 777s, what is the probability that the seat is a Business Class seat, assuming that all seats have an equal chance of being the last one available?

Correct Answer: 1/6 or .166 or .167

Explanation:

1/6 or.166 or .167

Difficulty: Easy

Category: Problem Solving and Data Analysis/Statistics and Probability

Getting to the Answer: This question requires concentration, but no complicated calculations. First, you need to identify the rows that contain information about the seating on the 777s, which are the bottom two rows. To find the probability that the seat is a Business Class seat, find the total number of seats in that category (in only the bottom two rows), and divide by the total number of seats on the planes (in only the bottom two rows):

Grid in your answer as 1/6 or .166 or .167.