From the information provided, the balance before the interest charge is $128. The interest charge itself is 2% per month. The amount charged as interest therefore is;
[tex]\begin{gathered} \text{Interest rate=2\% (or 0.02)} \\ \text{Outstanding balance=128} \\ \text{Amount of interest=}\frac{2}{100}\times128 \\ \text{Amount of interest=0.02 x 128} \\ \text{Amount of interest=2.56} \end{gathered}[/tex]The interest charge is $2.56 per month
