Education Technology


Published on 08/29/2011

Activity Overview

Students are led through the development of the formula for finding n objects taken n at a time and then n objects taken r at a time.

Key Steps

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    Students investigate factorials and the fundamental counting principle. They evaluate given expressions by using the factorial symbol "!".

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    Problem 2 also gives students the opportunity to explore all possible outcomes of spinning a spinner and flipping a coin.

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    Students move onto Problem 3 where they find the number of ways n objects can be taken r at a time. They explore and define permutations by listing all the ways the letters a, b, and c can be arranged.