Seatbelts II Police estimate that 80% of drivers nowwear their seatbelts. They set up a safety roadblock,stopping cars to check for seatbelt use.a) How many cars do they expect to stop before finding adriver whose seatbelt is not buckled?b) What’s the probability that the first unbelted driver isin the 6th car stopped?c) What’s the probability that the first 10 drivers are allwearing their seatbelts?d) If they stop 30 cars during the first hour, find the mean and standard deviation of the number of drivers ex-pected to be wearing seatbelts. e) If they stop 120 cars during this safety check, what’sthe probability they find at least 20 drivers not wearingtheir seatbelts?

Seatbelts II Police estimate that 80% of drivers now
wear their seatbelts. They set up a safety roadblock,
stopping cars to check for seatbelt use.
a) How many cars do they expect to stop before finding a
driver whose seatbelt is not buckled?
b) What’s the probability that the first unbelted driver is
in the 6th car stopped?
c) What’s the probability that the first 10 drivers are all
wearing their seatbelts?
d) If they stop 30 cars during the first hour, find the mean

and standard deviation of the number of drivers ex-
pected to be wearing seatbelts.

e) If they stop 120 cars during this safety check, what’s
the probability they find at least 20 drivers not wearing
their seatbelts?