Combinatorial Analysis: Visualizing Basic Counting Principle through a Problem

Problem:

The problem can be found on "First Course in Probability by Sheldon Ross".

A college planning committee consists of 3 freshmen, 4 sophmores, 5 juniors, and 2 seniors. A subcommittee of 4, consisting of 1 person from each class, is to be chosen. How many different subcommittee are possible?

Visualization and Explanation:

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