A researcher at a large university wanted to investigate if

A researcher at a large university wanted to investigate if a student\'s seat preference was related in any way to the gender of the student. The researcher divided the lecture room into three sections (1-front, middle of the room, 2-front, sides of the classroom, and 3-back of the classroom, both middle and sides) and noted where his students sat on a particular day of the class. The researcher\'s summary table is provided below. Suppose a person sitting in the front, middle portion of the class is randomly selected to answer a question. Find the probability the person selected is a female. A fast-food restaurant chain with 700 outlets in the United States described the geographic location of its restaurants with the accompanying table of percentages. A restaurant is to be chosen at random from the 700 to test market a new style of chicken. Given that the restaurant is located in

Solution

Answer : C 15/31

P(Person sitting in front,middle of the class) = 31/72

This is a conditional probability:

P(Female / Person sitting in front,middle of the class)

= P(Female AND Person sitting in front,middle of the class)/P(Person sitting in front,middle of the class)

= (15/72)/(31/72)

= 15/31 Answer C