Question

The cost of textbooks for a school increases with the average class size. Identify the independent and dependent quantity in the situation.

average class size; cost

cost; number of classes

cost; average class size

number of classes; average class size

Answer 1

average class size; cost

this is going to be your answer

Answer 2

average class size; cost

A variable is an object which is to be measured in a study either manipulated or the outcome of the study.
Independent variable is the variable which can be manipulated or controlled.
Dependent variable is the variable-outcome which is yielded after the independent variable or aimed variable.

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