The following table gives projections of the population of a country from 2000 to 2100. Answer parts (a) through (c).

| Year | Population (millions) |
|------|-----------------------|
| 2000 | 2795 |
| 2010 | 3059 |
| 2020 | 3348 |
| 2030 | 3568 |
| 2040 | 3829 |
| 2050 | 4134 |
| 2060 | 4375 |
| 2070 | 4652 |
| 2080 | 5056 |
| 2090 | 5418 |
| 2100 | 5749 |

(a) Find a linear function that models the data, with [tex]\( x \)[/tex] equal to the number of years after 2000 and [tex]\( f(x) \)[/tex] equal to the population in millions.

[tex]\[ f(x) = \square x + \square \][/tex]

(Use integers or decimals rounded to three decimal places as needed.)



Answer :

To model the data using a linear function, we need to find the slope and the intercept of the line [tex]\( f(x) = mx + b \)[/tex], where [tex]\( x \)[/tex] is the number of years after 2000 and [tex]\( f(x) \)[/tex] is the population in millions.

Given the data points:
- Year 2000 (which corresponds to [tex]\( x = 0 \)[/tex]) has a population of 2795 million.
- Year 2010 ([tex]\( x = 10 \)[/tex]) has a population of 3059 million.
- Year 2020 ([tex]\( x = 20 \)[/tex]) has a population of 3348 million.
- Year 2030 ([tex]\( x = 30 \)[/tex]) has a population of 3568 million.
- Year 2040 ([tex]\( x = 40 \)[/tex]) has a population of 3829 million.
- Year 2050 ([tex]\( x = 50 \)[/tex]) has a population of 4134 million.
- Year 2060 ([tex]\( x = 60 \)[/tex]) has a population of 4375 million.
- Year 2070 ([tex]\( x = 70 \)[/tex]) has a population of 4652 million.
- Year 2080 ([tex]\( x = 80 \)[/tex]) has a population of 5056 million.
- Year 2100 ([tex]\( x = 100 \)[/tex]) has a population of 5749 million.

By performing linear regression on these data points, we find that the slope [tex]\( m \)[/tex] and the intercept [tex]\( b \)[/tex] are:

[tex]\[ m \approx 28.786 \, \text{(rounded to three decimal places)} \][/tex]
[tex]\[ b \approx 2732.357 \, \text{(rounded to three decimal places)} \][/tex]

Therefore, the linear function that models the data is:
[tex]\[ f(x) = 28.786x + 2732.357 \][/tex]

So the function [tex]\( f(x) \)[/tex] that models the population in millions [tex]\( x \)[/tex] years after 2000 is:
[tex]\[ f(x) = 28.786x + 2732.357 \][/tex]

This function can now be used to estimate the population at any given year after 2000.