Lesson 07

In a survey, participants were asked how much confidence they had in the economy. The results were as follows: Response Number A great deal 3,945 Some 7,427 Hardly any 12,340 What is the probability that a sampled person has either some confidence or a great deal of confidence in the economy? Write only a number as your answer. Round to two decimal places (for example 0.43). Do not write as a percentage.

0.48

In a survey of 553 likely voters in a certain city, 296 said that they planned to vote to reelect the incumbent mayor. What is the probability that a surveyed voter plans to vote to reelect the mayor? Write only a number as your answer. Round to two decimal places (for example: 0.43). Do not write as a percentage.

0.54

An automobile insurance company divides customers into three categories: good risks, medium risks, and poor risks. Assume that of a total of 12,472 customers, 7,301 are good risks, 1,785 are medium risks, and the rest are poor risks. As part of an audit, one customer is chosen at random. What is the probability that the customer is not a poor risk? Write only a number as your answer. Round to two decimal places (for example: 0.43). Do not write as a percentage.

0.73

The General Social Survey asked 46,349 women how many children they had. The results were as follows. Number of Children = Number of Women 0 = 12,656 1 = 7,438 2 = 11,290 3 = 7,143 4 = 3,797 5 = 1,811 6 = 916 7 = 552 8 or more = 776 Using a cutoff value of 0.05, which of the following events are considered unusual? 1.Not Unusual 2.Unusual

__1__Having 3 children __1__Having 0 children __1__Having 2 children __2__Having 7 children __1__Having 1 child __2__Having 5 children __1__Having 4 children __2__Having 6 children __2__Having 8 or more children

Assume that a fair die is rolled. The sample space is {1, 2, 3, 4, 5, 6}, and all outcomes are equally likely. Find the following probabilities. ____P(4) ____P(8) ____P(Greater than 4) ____P(Odd number) ____P(Greater than 0) ____P(Less than 5) 1.1/6 2.1/2 3.2/3 4.1/3 5.0 6.1

__1__P(4) __5__P(8) __4__P(Greater than 4) __2__P(Odd number) __6__P(Greater than 0) __3__P(Less than 5)

Match each of the following: ____Event ____Sample Space ____P(A) ____Law of Large Numbers ____Unusual Event 1.The collection of all possible outcomes of a probability experiment. 2.An outcome or collection of outcomes from a sample space. 3.As a probability experiment is repeated, the proportion of times that a given outcome occurs will approach its probability. 4.Denotes the probability of event A and must always be between 0 and 1, inclusive. 5.An event whose probability is small. Most often, the cutoff value is 0.05.

__2__Event __1__Sample Space __4__P(A) __3__Law of Large Numbers __5__Unusual Event