1. Suppose that a company selects two people who work independently inspecting two-by-four timbers. Their job is to identify low-quality timbers. Suppose that the probability that an inspector does not identify a low-quality timber is 0.20. What is the probability that both inspectors do not identify a low-quality timber?
1. The following data represents the number of rooms in a random sample of U.S. housing units.
Rooms
Frequency
One
5
Two
11
Three
88
Four
183
Five
230
Six
204
Seven
123
Eight or more
156
(a) What is the probability that a randomly selected housing unit has four or more rooms?
(b) What is the probability that a randomly selected housing unit has fewer than eight rooms?
(c) What is the probability that a randomly selected housing unit has from four to six (inclusive) rooms?
(d) What is the probability that a randomly selected housing unit has at least two rooms?
2. Among 21- to 25-year-olds, 29% say they have driven while under the influence of alcohol. Suppose that three 21- to 25-year-olds are selected at random.
(a) What is the probability that all three 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?
(a) What is the probability that none of the three has driven while under the influence of alcohol?
1. Calculate the value of the following
a) 7!
b) 7P2
c) 9P7
d) 9C2
2. A certain compact disc player randomly plays each of 10 songs on a CD. Once a song is played, it is not repeated until all the songs on the CD have been played. In how many different ways can the CD player play the 10 songs?