Contextualization

Theoretical Introduction

Mathematics is a discipline that has many concepts and methods. Among them, two of the most important are the multiplication and division of decimal numbers. These concepts are the basis for many other topics in mathematics.

Multiplying decimal numbers is an extension of multiplying integers. A decimal number is simply a number that has a fractional part, represented by digits to the right of the decimal point. Multiplying decimal numbers follows the same basic rules as multiplying integers, but has an additional step to determine the location of the decimal point in the result.

Dividing decimal numbers is also similar to dividing integers. Again, the main difference is determining where the decimal point goes in the quotient, or result. In some cases, it is also necessary to add zeros to the right of the fractional part of the dividend, or number to be divided.

Importance and Applications

The ability to multiply and divide decimal numbers is vital in many areas of everyday life, as well as in many professions. For example, when shopping, you may need to multiply the unit price by a quantity to find the total cost. When you divide a cake or a pizza, you are dividing a whole into parts, which is an application of division.

Furthermore, many professions require the use of multiplication and division of decimal numbers. Engineers use these operations to perform critical calculations. Scientists use them to measure and quantify observations. Those in finance use them to calculate interest, investment returns, and other vital measures.

Practical Activity

Activity Title: "Decimal Market"

Project Objective

This interdisciplinary project aims to reinforce students' understanding of multiplying and dividing decimal numbers, as well as develop financial planning, ethical, and interpersonal skills through a market simulation.

Detailed Project Description

Participants must work in groups of 3 to 5 people. Each group will be responsible for managing a "store" in our "Decimal Market". The store can sell any type of item the group chooses, as long as the prices are in decimal numbers.

To do this, the groups must:

• Establish a list of products, with at least 10 items, each with prices in decimal numbers.
• Define a strategy for purchasing products from other stores considering an "initial budget" provided by the teacher.
• Manage sales to other teams.

This project will extend over a week, with students working in groups for at least 12 hours in total, both at school and at home.

Necessary Materials

1. Paper and pencil for notes and calculations.
2. A price list for each store.
3. A "check" with the initial budget for each group.

Step-by-Step Guide for the Activity

1. Formation of groups and definition of what type of store each group will manage.
2. Each group must create a list of at least 10 products for their store, with prices in decimal numbers.
3. The teams receive the initial "budget" and must plan which products to buy from other stores.
4. The groups visit each other's stores and make purchases, noting on their "check" the value of each purchase and subtracting it from the budget.
5. Each group must monitor their sales and calculate the profit obtained.
6. At the end of the project, each group must present a report containing all sales and purchase calculations and what the profit or loss was.

Project Deliverables

• Store Product: Each team must deliver the list of products from their store with prices in decimal numbers.
• Record of Purchases and Sales: Each team must keep a detailed record of all purchases and sales made.
• Final Report: Each team must prepare a report that includes: (1) an introduction that explains the idea behind the project and its real-world applications; (2) a detailed description of the project, including strategies used, problems encountered, and how they were solved; (3) the conclusion, in which they should express what they learned from the project and how this experience can be useful for them in the future; (4) the bibliography, listing all sources consulted for the work.

Students should pay special attention to writing the report, using the knowledge acquired in the Portuguese Language discipline to present a clear, cohesive, and coherent text.