A statistics teacher has 40 students in his class, 23 feld
and 17 males. At the beginning of class on a Monday, the
teacher planned to spend time reviewing an assignment due
that day. Unknown to the teacher, only 19 of the females and
11 of the males had completed the assignment. The teacher
plans to randomly select students to do problems from the
assignment on the whiteboard.
(a) What is the probability that a randomly selected
student has completed the assignment?
(b) Are the events "selecting a female" and "selecting a
student who completed the assignment" indepen-
dent? Justify your answer.