In a certain Algebra and Trigonometry class, there are 5 male freshmen, 4 female freshmen, 4 male sophomores, and 7 female sophomores. If a person is selected randorly from the group, find the probability that the selected person is a freshman or female.

Answer 1

To find the probability that the selected person is a freshman or female, we need to find the total number of freshmen and the total number of females, and then subtract the number of students who are both freshmen and females (to avoid double-counting).

There are 5 male freshmen, 4 female freshmen, 4 male sophomores, and 7 female sophomores. So there are 5+4= <<5+4=9>>9 freshmen and 4+7= <<4+7=11>>11 females.

However, we have counted the 4 female freshmen twice, so we need to subtract 4 from the total number of freshmen and females (9+11-4).

Total number of freshmen or females = 9+11-4 = 16.

Therefore, the probability that the selected person is a freshman or female is 16/<<5+4+4+7=20>>20 = 4/5 = 0.8, or 80%.