A review of the records at Lander Community College revealed

A review of the records at Lander Community College revealed the following ethnic breakdown of the student population: Caucasian 1200 Black 600 Hispanic 200 Asian 80 Native American 60 Other 20 a) What is the probability that a randomly selected student is either Caucasian or Black? b) What is the probability that the selected student is not a member of either of the two largest categories?

Solution

Total number of students = 1200 + 600 + 200 + 80 + 60 + 20 = 2160

a. Number of Caucasian or Black students is 1200 + 600 = 1800

Therefore, the probability that a randomly selected student is either Caucasian or Black is given by

Number of Caucasian or Black students/Total number of students = 1800/2160 = 0.8333

b. Probability that the selected student is not a member of either of the two largest categories = 1 - Probability that a randomly selected student is either Caucasian or Black = 1 - 0.8333 = 0.1667