Mean Family Size. Use the following information for Exercises 72–74: According to the Statistical Abstract of the United States, the mean family size in 2010 was 3.14 persons, reflecting a slow decrease since 1980, when the mean family size was 3.29 persons. Has this trend continued to the present day? Suppose a random sample of 225 families taken this year yields a sample mean size of 3.05 persons, and suppose we assume that the population standard deviation of family sizes is 1 person.

Question 9.180

image 74. Refer to Exercises 72 and 73, What if the 3.05 persons had been a typo, and the actual sample mean was 3.00 persons? How would this have affected the following?

  2. The -value
  3. The conclusion