Answer
See the explanation
Work Step by Step
a.The formula for the cost of purchasing and using the photocopier for n months is that, the cost of purchasing the photocopier plus the maintenance fee plus the cost of each copy times the number of copy the intend to make each month times n.
$C(n)_p=5800+25n+0.003\times8000n=265n+5800$
b.The formula for the cot of renting the photosopier for n months is that, the cost of the rent plus the cost of the each copy times the number of copy the intend to make each month times n.
$C(n)_r=95n+0.06\times8000n=575n$
c.
$\begin{array}{lll}
n & C(n)_p&C(n)_r\\
1year/12month&8980&6900\\
2year/24month&12160&13800\\
3year/36month&15340&20700\\
4year/48month&18520&27600\\
5year/60month&21700&34500\\
6year/72month&24880&41400
\end{array}$
d.$C(n)_p=C(n)_r$,
$265n+5800=575n$,
$310n=5800$,
$n=18.71$, $n=19$.
After $19^{th}$ month of use, the cost would be the same for both method.
