Confused on this anyone can explain the answer to me?

Answer:
$397.51.
Step-by-step explanation:
Note the finance rate is levied on the balance at the end of each payment period.
Balance after the $45 payment = 95.85 -45 = $50.85.
Balance after adding the 1.5% credit charge = 50.85*1.015 = $51.61.
Plus New Charges = 51.61 + 345.90
= $397.51.