(Solved): EXAMPLE 3 The linear equation C=1.65429t-2938.07 models the average CO_(2), carbon dioxide, level (m ...

EXAMPLE 3 The linear equation

models the average

, carbon dioxide, level (measured in parts per million) in the atmosphere at an observatory from 1980 to 2008. Use the linear model to estimate the average

level for 1987 and to predict the level for the year 2017. According to this model, when will the

level exceed 430 parts per million? SOLUTION Using

with

, we estimate that the average

level in 1987 was xample

(rounded to two decimal This is an example of interpolation because we have estimated a value between observed values. With

, we get

(