Constructing Algebraic Models Question 6

The textbooks produced by a publisher have pages that are 0.1 millimeter thick and a front cover and a back cover that each are 1 millimeter thick. Which of the following gives the total thickness $f(n)$ , in millimeters, of a closed book that has $n$ pages?

f(n)=2+n

f(n)=2+0.1n

f(n)=0.2+0.1n

f(n)=0.1+0.1n

Approach

The thickness of the cover and back cover are fixed, but the thickness is increased for every page.

f(n)= \underbrace{1}_\text{front cover} + \underbrace{1}_\text{back cover} + \underbrace{0.1(n)}_\text{0.1 mm per page}

\boxed{f(n)= 2+0.1n }