Value of the expression in which we replaced each of the variables with numbers from their defined domains.

Talking about the value of a digit is a short form to refer to the **numerical value associated with a digit** in the case of a number that only has one digit.

### Example

Consider the algebraic expression 2*x* + 4*xy*\(^{2}\) in which the variables x and y take values from the set of integers.

The numerical value of this expression, when *x* = 5 and *y* = 10, is 2010, because: 2 × 5 + 4 × 5 × 10^{2} = 2010.

### Educational Note

When a number has more than one digit, the expression “*the sum of the digits of a number*” should be replaced by “*the sum of the numerical values associated with each digit in a number*“.