Answer: Fractional reserve banking
Step-by-step explanation:
Fractional-reserve banking is a common form of banking that is practised by commercial banks worldwide. It involves banks in every part of the world. Fractional reserve banking is the acceptance of deposits from customers and then making loans to borrowers, while the reserve a fraction of the deposit liabilities of the bank is held.
From the question, Maria makes a deposit of $10,000 into the savings account she uses at Smalltown Bank and the bank holds 20% of the deposit she made and later lends the remaining $8,000 to another customer is an example of fractional reserve banking.