In a large section of a statistics class, the points for the final exam are normally distributed, with a mean of 72 and a standard deviation of 9. Grades are to be assigned according to the following rule:
- The top 10% receive A’s.
- The next 20% receive B’s.
- The middle 40% receive C’s.
- The next 20% received D’s.
- The bottom 10% receive F’s.
Find the lowest score on the final exam that would qualify a student for an A, a B, a C, and a D. (Round your answers to two decimal places.)
Final Exam GradesAND20OK1El4080BOB APoints scored on final examFIGURE FOR EXERCISE 42