In Example 6 we used data from 1920 to 2020 and found that the life span in the
ID: 3197724 • Letter: I
Question
In Example 6 we used data from 1920 to 2020 and found that the life span in the United States depended on the year of birth according to the equation
L(x) = 11.027 + 14.304 ln(x)
where x is the number of years after 1900. Using data from 1920 to 1989, the model
?(x) = 11.616 + 14.144 ln(x)
where x is the number of years after 1900, predicts life span as a function of birth year. Use both models to predict the life spans for people born in 1995 and in 2020. (Round your answers to two decimal places.)
model L: 1995 = years model L: 2020 = years model ?: 1995 = years model ?: 2020 = yearsExplanation / Answer
model L : 11.027 + 14.304ln(x)
For year 1995, x = 1995 - 1900 = 95
=> Expected Life = 11.027 + 14.304 ln(95) = 76.165 years
For year 2020, x = 2020 - 1900 = 120
=> Expected Life = 11.027 + 14.304 ln(120) = 79.507 years
model ? : 11.616 + 14.144ln(x)
For year 1995, x = 1995 - 1900 = 95
=> Expected Life = 11.616 + 14.144*ln(95) = 76.026 years
For year 2020, x = 2020 - 1900 = 120
=> Expected Life = 11.616 + 14.144*ln(120) = 79.33 years