Problem 37 - Applied Statistics and Probability for Engineers

Question

New designs for a wastewater treatment tank have proposed three possible shapes, four possible sizes, three locations for input valves, and four locations for output valves. How many different product designs are possible?

Step-by-Step Solution

Answer

There are 144 different product designs possible.

Step 1: Understand the Problem

We need to count the total number of different product designs possible by considering the combinations of the given attributes: shapes, sizes, input valve locations, and output valve locations.

Step 2: Identify the Number of Options for Each Attribute

There are three options for the shape of the tank, four options for the size, three options for the location of input valves, and four options for the location of output valves.

Step 3: Use the Multiplication Principle

The total number of combinations of the attributes can be found by multiplying the number of options for each attribute. This is because each choice is independent of the others. Therefore, the number of different product designs is given by the multiplication of available options: \[ 3 \times 4 \times 3 \times 4 \]

Step 4: Calculate the Total Number of Designs

Perform the multiplication to calculate the total number of possible designs:\[ 3 \times 4 = 12 \]\[ 12 \times 3 = 36 \]\[ 36 \times 4 = 144 \]

Step 5: Write the Final Answer

Based on our calculations, the total number of different product designs possible is 144.

Key Concepts

Multiplication Principle

The Multiplication Principle is an essential part of combinatorial analysis. It is used to determine the number of possible outcomes when there are several choices or factors involved, each with a set amount of options. The principle simplifies the complex process of counting by providing a straightforward method: multiplying the number of choices for each factor.For example, in the exercise, we have:

• Three shapes
• Four sizes
• Three input valve locations
• Four output valve locations

Each of these choices is independent, meaning the decision for the shape does not affect the size, and so on.Thus, we apply the multiplication principle: Multiply the number of choices for each attribute to find the total combinations. This gives us the total designs possible: \[ 3 \times 4 \times 3 \times 4 = 144 \]By using this principle, complex combination problems become easier to manage. The primary requirement is that each choice must be independent of the others, which applies to product designs perfectly.

Combinations

Combinations are crucial in understanding how different attributes come together to form unique configurations. Unlike permutations, where the order affects the outcome, combinations rely solely on the selection, regardless of order. In the exercise about wastewater treatment tanks: - Each combination is made of different features: shapes, sizes, input, and output valves. - By selecting one option from each category, you form a single unique product design. Combinations can be calculated using the multiplication principle if every attribute is independent and each selection results in a different combination. It's important to note: - Combinatorial analysis differs when order matters (permutations) or doesn't matter (combinations). - In our exercise, the order of selection isn’t important, making it purely a problem of combinations. This concept helps in categorizing and counting distinct groups formed by selections from multiple categories.

Problem Solving Steps

Problem solving in combinatorics involves systematic steps to ensure each aspect of the problem is correctly interpreted and addressed. To effectively solve the exercise, we apply a set sequence of actions:1. **Understand the Problem:** Analyze what is being asked. In our case, it was determining the number of possible tank designs.
2. **Identify Options:** Determine how many choices are available for each attribute. We had separate counts for shapes, sizes, and valve locations.
3. **Apply the Multiplication Principle:** Calculate total combinations by multiplying the number of choices per attribute.
4. **Perform Calculations:** Execute the multiplication step-by-step to avoid errors and verify your calculations: - Multiply the shape and size options: \( 3 \times 4 = 12 \) - Then include input valve locations: \( 12 \times 3 = 36 \) - Finally, include output valve locations: \( 36 \times 4 = 144 \)5. **Conclusion:** Arrive at the final answer; here, the number of possible designs is 144.These steps provide a structured framework that enhances clarity and accuracy, essential in solving combinatorial problems effectively.