Sub addtwonum()
 'this subprog adds two numbers (to single precision accuracy)
 ' 
 'declare variables for efficient use of computer resources
  Dim sinNum1 As Single
  Dim sinNum2 As Single
  Dim sinTotal As Single
 '
 'input
  'INPUT "Enter the first number .. " ; sinNum1   'qbasic
  'INPUT "Enter another number .... " ; sinNum1   'qbasic
  sinNum1 = InputBox("Enter the first number .. ")  'vba
  sinNum2 = InputBox("Enter another number .... ")  'vba
 '
 'calculations
        sinTotal = sinNum1 + sinNum2   'the algorithm
 '  
 'output
  'PRINT "The sum of the two numbers is .. " ; sinTotal  'qbasic
  MsgBox "The sum of the two numbers is .. " & sinTotal  'vba
'
End Sub