Quality assurance Boundary value analysis Test case design Public



An informational calculator for term deposit interests needs to be tested. For a given deposit amount and the client’s age, the calculator shows the annual interest rate.

The following rules apply:

  • The minimum deposit amount is $100.00.
  • Regular interest rates don’t apply for deposits greater than $10,000.00.
  • The annual interest rate depends on the deposit amount as follows:
    Deposit amountAnnual interest rate
    $100.00 - $999.991.0%
    $1,000.00 - $4,999.991.3%
    $5,000.00 - $10,000.001.5%
  • Only adults (i.e. 18 and older) are eligible to open a term deposit account.
  • Clients 60 and older have the applicable annual interest rate increased by 20%.

How many test cases are required to form an adequate test suite for this app? An adequate test suite should test all boundary values.