Given that the credit card has an APR of 21.8%=0.218.
The previous balance in the first month is $1300. The payment is $300 and the purchase is equal to $500.
now, we need to find the finance charges by the following formula:
[tex]\frac{APR}{12}\times(PreviousBalance-payments+purchases)[/tex]
Substitute the given values in the formula:
[tex]\frac{0.218}{12}\times(1300-300+500)=27.25[/tex]
now, the new balance for the first month will be equal to Previous balance-payments+purchases+finance charges
[tex]1300-300+500+27.25=1527.25[/tex]
the same calculation goes for the second month. the previous balance for second month is $1527.25. The payment is $300 and the purchase is equal to $600.
The finance charges for the second will be:
[tex]\frac{0.218}{12}\times(1527.25-300+600)=33.20[/tex]
So, the new balance for the second month will be
[tex]1527.25-300+600+33.20=1860.45[/tex]
Now, you can fill the table your self.