Arithmetic operators add, subtract, multiply, and divide numeric operands in arithmetic expressions.
The simplest arithmetic expression is a single numeric constant, variable, or function. A simple arithmetic expression can combine two operands using an arithmetic operator. More complicated arithmetic expressions are formed by combining simple expressions using arithmetic operators.
If a string value is used in an arithmetic expression, the BASIC run-time package attempts to convert it into a number. If it fails, 0 is used and a warning displays.
If a string value containing only numeric characters is used in an arithmetic expression, it is evaluated as a decimal number. If a string value containing nonnumeric characters is used in an arithmetic expression, a warning message displays and zero is assumed for the string value.
total = (invoice.amount - discount) + tax