At the end of the first year, the correct formula is this one:

The second year, we add r times the above amount, we get:

Iterating the process, we get the general formula of any number of years:
Answer:
$280 dollars
Step-by-step explanation:
When they were leaving

When they returned home, they brought 196 Euros.

They brought back $280 dollars to the United States.
Answer:
A commom denominators
Step-by-step explanation: