Name_________________________________
5.3 Examples
1.
What is the probability of obtaining 4 ones in a row when rolling a fair, six-sided die?
2.
Suppose that your financial advisor has recommended two stocks, each of which has a 60%
chance of increasing value over the next year. Assuming that the performance of the two stocks
are independent of each other, what is the probability that both stocks will rise of over the next
year? What is the probability that at least one stock will not increase in value?
3.
The probability that a randomly selected 40-year-old female will live to be 41 years old is
.99856.
a) What is the probability that two randomly selected 40-year-old females will live to be 41?
b) What is the probability that five randomly selected 40-year-old females will live to be 41?
c) What is the probability that at least one of the five randomly selected 40-year-old females
would not live to be 41?
4. Among 21-25-year-olds, 29% say that they have driven under the influence of alcohol. Suppose
that 3 21-25-year-olds are selected at random.
a) What is the probability that all 3 have driven while under the influence of alcohol?
b) What is the probability that at least one has not driven while under the influence of alcohol?