Question

A student can select one of 6 different mathematics books, one of 3 different chemistry books and one of 4 different science books. In how many different ways can a student select a book of mathematics, a book of chemistry and a book of science?

Answer 1

By the rule of product, there are 6 * 3 * 4 = 72 different ways.

References: https://en.wikipedia.org/wiki/Rule_of_product