Below are bivariate data giving birthrate and life expectancy information for each of twelve countries. For each of the countries, both , the number of births per one thousand people in the population, and , the female life expectancy (in years), are given. Also shown are the scatter plot for the data and the least-squares regression line. The equation for this line is .

Birthrate, x

(number of births per 1000 pop.)

Female life expectancy, y

(in years)

16.1

75.8

49.7

52.4

49.8

61.4

50.5

59.1

45.3

57.4

18.3

72.0

25.6

74.1

35.5

66.4

13.8

72.8

27.4

71.7

40.5

65.5

28.8

63.7

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x

10

15

20

25

30

35

40

45

50

55

60

y

50

55

60

65

70

75

80

85

0

Figure1

Based on the sample data and the regression line, answer the following:

1. Fill in the blank: For these data, female life expectancies that are less than the mean of the female life expectancies tend to be paired with birthrates that are _____ the mean of the birthrates.

Choose onegreater thanless than

2. According to the regression equation, for an increase of one (birth per 1000 people) in birthrate, there is a corresponding decrease of how many years in female life expectancy?

3. From the regression equation, what is the predicted female life expectancy (in years) when the birthrate is 13.8 births per people? (Round your answer to at least one decimal place.)

4. From the regression equation, what is the predicted female life expectancy (in years) when the birthrate is 19.9 births per people? (Round your answer to at least one decimal place.)