A study investigated the relationship among annual tire sales T in thousands, automobile registrations A in millions, and personal disposable income I in millions of dollars. Representative data for three different years are shown in the table. The data were modeled by T = aA + bI + c, where a, b, and c are constants.

(a) Use the data to write a system of linear equations whose solution gives a, b, and c. 

(b) Solve this linear system. Write a formula for T, as T = aA + bI + c. 

(c) If A = 118 and I = 311, predict T. 

Transcribed Image Text:

T 10,170 113 15,305 133 21,289 155 1937 1 308 622