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Use the following information to answer the next 12 exercises: The U.S. Center for Disease Control reports that the mean life expectancy was 47.6 years for whites born in 1900 and 33.0 years for nonwhites. Suppose that you randomly survey death records for people born in 1900 in a certain county. Of the 124 whites, the mean life span was 45.3 years with a standard deviation of 12.7 years. Of the 82 nonwhites, the mean life span was 34.1 years with a standard deviation of 15.6 years. Conduct a hypothesis test to see if the mean life spans in the county were the same for whites and nonwhites.

19. Is this a test of means or proportions?

Short Answer

Expert verified

The nonwhites and whites in the country born in 1990 have the same mean life span, hence this test is for the means.

As a result, the means are examined.

Step by step solution

01

Given information

According to the US Centers for Disease Control, the average life expectancy for whites born in 1900 was 47. years and 33 years for nonwhites. Assume you survey death records for people born in 1900 in a specific county at random. The average life duration of the 124 whites was 45.3 years, with a standard deviation of 12.7 years. The average life duration of the 82 nonwhites was 34.1 years, with a standard deviation of 15.6 years. Conduct a hypothesis test to check if whites and nonwhites in the county have the same average life lengths.

02

Is this a test of means or proportions? 

This test is to test the means, that is, the mean life spans in the country born in 1900 for the whites and nonvhites.

Hence the means are tested.

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Most popular questions from this chapter

96. Some manufacturers claim that non-hybrid sedan cars have a lower mean miles-per-gallon (mpg) than hybrid ones. Suppose that consumers test 21 hybrid sedans and get a mean of 31 mpg with a standard deviation of seven mpg. Thirty one non-hybrid sedans get a mean of 22mpg with a standard deviation of four mpg. Suppose that the population standard deviations are known to be six and three, respectively. Conduct a hypothesis test to evaluate the manufacturers claim.

Use the following information to answer the next 12 exercises: The U.S. Center for Disease Control reports that the mean life expectancy was 47.6 years for whites born in 1900 and 33.0 years for nonwhites. Suppose that you randomly survey death records for people born in 1900 in a certain county. Of the 124 whites, the mean life span was 45.3 years with a standard deviation of 12.7 years. Of the 82 nonwhites, the mean life span was 34.1 years with a standard deviation of 15.6 years. Conduct a hypothesis test to see if the mean life spans in the county were the same for whites and nonwhites.

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