$\begin{array}{lll}\text { September 1 } & \text { Previous Balance } & \$ 40.33 \\ \text { September 11 } & \text { Purchases } & \$ 477.03 \\ \text { September 20 } & \text { Payment } & \$ 100.00 \\ \text { September 25 } & \text { Purchases } & \$ 220.16\end{array}$
Part 1 of 3
(a) Find the average daily balance. Round the answer to the nearest cent.
The average daily balance is $\$ 365.72$.
Part 2 of 3
(b) Find the finance charge for the month. The interest rate is $1.8 \%$ per month on the average daily balance. Round the answer to the nearest cent.
The finance charge for the month is $\$ 6.58$.
Part: $2 / 3$
Part 3 of 3
(c) Find the new balance on October 1.

Step 1 ：Given the previous balance of \(\$40.33\), purchases of \(\$477.03\) and \(\$220.16\), a payment of \(\$100.00\), and a finance charge of \(\$6.58\).

Step 2 ：To find the new balance on October 1, we need to add the previous balance, the purchases, and the finance charge, then subtract the payment.

Step 3 ：Using the formula: \(\text{new balance} = \text{previous balance} + \text{purchases1} + \text{purchases2} + \text{finance charge} - \text{payment}\)

Step 4 ：Substitute the given values into the formula: \(\text{new balance} = 40.33 + 477.03 + 220.16 + 6.58 - 100.00\)

Step 5 ：Calculate the new balance: \(\text{new balance} = 644.10\)

Step 6 ：\(\boxed{\text{The new balance on October 1 is }\$644.10}\)