Final answer:
The interest calculated from the last partial payment is added to the adjusted balance when using the U.S. Rule to calculate compound interest.
Step-by-step explanation:
When using the U.S. Rule to calculate compound interest, the interest calculated from the last partial payment is added to the adjusted balance.
For example, let's say you have a loan with a principal of $1000, an interest rate of 5%, and a term of 1 year. If you make a partial payment of $500 at the end of 6 months, the interest calculated on that partial payment would be added to the adjusted balance.