Question 1
According to the 2011 National Occupant Protection Use Survey, only 84% of drivers wear seat belts. Calculate the probabilities that out of 4 randomly selected drivers,
a) Only one of the drivers is wearing a seatbelt
b) Half of the drivers are wearing seatbelts
c) All of the drivers are wearing seatbelts
Question 2
Find the proportion under a standardized normal curve in the following cases:
a) Less than -2.50
b) Greater than 1.60
c) Between -1.96 and 1.96
d) Less than -1.96 or greater than 1.9