Answer
See below
Work Step by Step
(a)
The total amounts to \[\$130888\]approximately and the total number of days billing period 30 days.
$\begin{align}
& \text{Average daily balance}=\frac{\text{Sum of unpaid balance for each day billing period}}{\text{No}\text{. of days in the billing period}} \\
& =\frac{\$130,888}{30}\\&=\$4362.93\\&\simeq\$4363\end{align}$
(b)
The rate of interest is $1.1percent$per month, Compute the interest to be paid on December 1 as follows:
\[\begin{align}
& I=Prt \\
& =\text{ }\!\!\$\!\!\text{4363}\!\!\times\!\!\text{0}\text{.011}\!\!\times\!\!\text{1}\\&=\frac{\text{}\!\!\$\!\!\text{4363}\!\!\times\!\!\text{1}\text{.1}\!\!\times\!\!\text{1}}{\text{100}}\\&=\text{}\!\!\$\!\!\text{47}\text{.99}\\&\simeq\$\text{48}\end{align}\]
Hence, the amount of interest is\[\$48\].
(c)
Compute the balance due on December 1 as shown below;
\[\begin{align}
& \text{Balance due}=\text{Unpaid balance on November 30}+\text{Interest} \\
& =\$4,485+\$48\\&=\$4,533\end{align}\]
(d)
The Balance due exceeds the amount$\$360$. Therefore, the customers must pay a minimum of $\frac{1}{36}$ balance due.
Compute the monthly payment as follows:
\[\begin{align}
& \text{Minimum}\,\text{Monthly}\,\,\text{Payment}=\,\text{Balance}\,\text{due}\,\text{ }\!\!\times\!\!\text{ }\frac{\text{1}}{\text{36}} \\
& =\,\$\,4533\,\times\frac{1}{36}\\&=\,\$\,125.9\\&\simeq\,\text{}\!\!\$\!\!\text{}\,\text{126}\,\text{approximately}\end{align}\]
Hence, the minimum monthly payment due by December 9 is\[\$97\].
