STATISTICS 3N03/3J04
Test #2 *
2004-11-04
Instructions
Aids permitted: any calculators, any mathematical or
statistical tables, and one sheet of notes (8.5" x 11", one side
only).
Questions
- Who
discovered the limit of the binomial distribution as n goes to infinity and p goes to zero? What was his full name?
- Because
not all airline passengers show up for their seats, an airline sells 125 tickets
for a flight that holds only 120 passengers. The probability that a
passenger does not show up is 0.1. What is the probability that the flight
departs with empty seats? State any assumptions you make.
- The amount of time a customer spends
waiting at an airport check-in counter is a random variable with mean 8.2
minutes and standard deviation 1.5 minutes. Suppose that a random sample
of 49 customers is observed. What is the probability that the average
waiting time in line for these customers is between 5 and 10 minutes?
State any assumptions you make.
- Failures of a testing instrument due
to biological contamination occur at random at a mean rate of 0.02 failures
per hour. What is the probability that the instrument does not fail in an
8-hour shift? State any assumptions you make.
- Define the following terms: parameter,
statistic, sampling distribution.