Problem 5 - Applied Mathematics: For the Managerial, Life, and Social Sciences

Question

A female executive selecting her wardrobe purchased two blazers, four blouses, and three skirts in coordinating colors. How many ensembles consisting of a blazer, a blouse, and a skirt can she create from this collection?

Step-by-Step Solution

Answer

The female executive can create 24 different ensembles from her collection of 2 blazers, 4 blouses, and 3 skirts, using the counting principle: \(2 \times 4 \times 3 = 24\).

Step 1: Determine the number of choices for each clothing item

For creating an ensemble, the executive needs to choose one item from each category of clothing: - Blazers: She has 2 blazers to choose from. - Blouses: She has 4 blouses to choose from. - Skirts: She has 3 skirts to choose from.

Step 2: Use the counting principle

We can use the counting principle to find the total number of ensembles. The counting principle states that the number of ways to make a series of choices is the product of the number of choices for each step. In this case, we have: - Number of choices for blazers: 2 - Number of choices for blouses: 4 - Number of choices for skirts: 3 Using the counting principle, let's multiply the number of choices for each clothing item: Total ensembles = number of blazer choices × number of blouse choices × number of skirt choices

Step 3: Calculate the total number of ensembles

Multiply the number of choices for each clothing item: Total ensembles = 2 blazers × 4 blouses × 3 skirts = \(2 \times 4 \times 3 = 24\) So, the female executive can create 24 different ensembles from her collection of blazers, blouses, and skirts.

Key Concepts

Understanding the Counting Principle

The counting principle is a fundamental concept in combinatorics that helps us determine the number of possible outcomes in a series of choices. It is sometimes referred to as the multiplication principle because it involves multiplying the number of options for each choice available.

For instance, in the wardrobe selection exercise, the female executive needs to make decisions from three categories of clothing: blazers, blouses, and skirts. By applying the counting principle, you multiply the number of available choices for each type of clothing item to find the total number of combinations possible.

• Blazers: 2 choices
• Blouses: 4 choices
• Skirts: 3 choices

Together, this gives us a multiplication of choices, \(2 \times 4 \times 3\), which equals 24. This means there are 24 possible combinations of outfits. The counting principle is useful in various real-life scenarios, such as menu options in a restaurant or choosing routes to travel, making it an essential part of mathematics education.

Exploring Permutations

Permutations deal with the arrangement of objects in a specific sequence or order. In the context of combinatorics, permutations consider that the order of selection matters, differing from combinations where the order is not important.

In the wardrobe example, permutations aren't directly applied because the order of the clothing items (which to choose first) doesn't affect the outcome of the ensemble. However, understanding permutations is crucial when order does matter. For example, if the executive needed to wear her blouses in a specific sequence throughout a week, the ordering of those blouses counts as permutations.

A typical formula for computing the number of permutations of \(n\) objects taken \(r\) at a time is given by \( P(n, r) = \frac{n!}{(n-r)!} \).
Understanding permutations is key in solving problems related to arrangement, travel scheduling, or organizing events, as it plays a vital role in mathematics education.

Combinatorics in Mathematics Education

Combinatorics is a field of mathematics that focuses on counting, arranging, and finding patterns in sets of numbers or objects. It often serves as a gateway to more advanced mathematical concepts because of its applicability to various problem-solving scenarios.

Incorporating combinatorics into mathematics education helps students develop critical thinking skills and offers them practical tools to solve complex life and academic problems. Topics such as the counting principle and permutations, as seen in the wardrobe exercise, are foundational for this branch of mathematics.

Educators use combinatorics to introduce students to concepts of probability, optimization, and algorithm design. By solving real-life problems like creating outfits or planning trips, learners discover the importance of mathematics beyond the classroom. Consequently, combinatorics forms an integral part of a balanced and comprehensive mathematics curriculum.