Assume the amount of time statistics students spent studying for the Math 10 final exam is exponentially distributed with a mean of 4.2 hours. Eighty percent (80 %) of students studied more than how many hours? a. 0.9
b. 3.4
c. 6.8
d. 7.6

Solve the problem by making up an equation. a man could arrive on time for an appointment if he drove the car at 40 mph; however, since he left the house 15 minutes late, he drove the car at 50 mph and arrive 3 minutes early for the appointment. how far from his house was his appointment?