Final answer:
The numerical factor of a multiplication expression that contains a variable is called a coefficient.
Step-by-step explanation:
The numerical factor of a multiplication expression that contains a variable is called a coefficient. A coefficient is a constant value that multiplies the variable in an algebraic expression or equation.
For example, in the expression 3x, the coefficient is 3. In the expression 2xy, the coefficient is 2. The coefficient represents the amount by which the variable is being scaled or multiplied.
It's important to note that in multiplication, the coefficient is not always a number. It can also be another variable or a combination of variables and numbers.