Public Class Foo

    Private baseTokenAmount As Int32 = 1

    Public Function GetNumberOfRequiredTokens(ByVal typeOfPerson As PersonType) As Int32

        Select Case typeOfPerson

            Case PersonType.Infant

                Throw New Exception("Too young to ride")

            Case PersonType.Child

                Return baseTokenAmount

            Case PersonType.Adolescent

                Return baseTokenAmount * 2

            Case PersonType.Adult

                Return baseTokenAmount * 3

            Case PersonType.Senior

                Throw New Exception("Too old to ride")

        End Select

    End Function

    Public Enum PersonType

        Infant

        Child

        Adolescent

        Adult

        Senior

    End Enum

End Class