7. A large school has the numbers categorized by grade and gender as shown in the table.
Grade 9 Grade 10 Grade 11 Grade 12
Gender
Male
Female
Grade
180
200
170
130
230
190
a. What is the probability that a student chosen at random will be a female?
220
180
Total
800
700
b. What is the probability that a student chosen at random will be a male grade 12 student?
c. What is the probability that a female student chosen at random will be a grade 12 student?
e. What is the probability that a grade 12 student chosen at random will be a male?
d. What is the probability that a student chosen at random will be a grade 12 student or a female student?
f. What is the probability that a student chosen at random will be a female and a grade 11 or grade 12 student?