The day she did make the payment is closest to June 20th.
Finance Charge = (Average Daily Balance * APR * Number of Days in Billing Cycle) / 365
We will use this to find out on which day Laura made the payment in June.
1. On June 1st, Laura had a balance of $606.40.
2. She made the payment of $55.25, so for the rest of the month, her balance was $606.40 - $55.25 = $551.15.
3. June has 30 days.
The Average Daily Balance:
= ($606.40 * 1 + $551.15 * 29) / 30
= ($606.40 + $15,981.35) / 30
= $16,587.75 / 30
= $552.925.
Finance Charge = (Average Daily Balance * APR * Number of Days in Billing Cycle) / 365
$5.71 = ($552.92.5 * 0.1204 * Number of Days in Billing Cycle) / 365
Solving for the Number of Days in Billing Cycle
Number of Days in Billing Cycle = ($5.71 * 365) / ($552.925* 0.1204)
= 31.3066256
= 31.3066256
= 31.