When considering algebraic expressions and problems, we know that there are two types of variables: dependent and independent variables.
An independent variable is a variable that represents a quantity that is being manipulated in an experiment. A dependent variable represents a quantity whose value depends on how the independent variable is manipulated.
From the question provided, the amount of pepperoni used is dependent on the number of pizzas made, since we are given 20 slices of pepperoni per pizza.
Therefore, the answer is TRUE.