Percentage: Notable Percentages | Traditional Summary
Contextualization
Percentages are a way to express fractions of a whole, allowing us to represent parts of a number or quantity in a more intuitive and practical way. In everyday life, we use percentages to understand and compare different parts of a total, such as store discounts, survey results, and even in sports, like ball possession in a soccer match. For example, if a product is 50% off, it means the price has been halved, making it easier to visualize the savings made on the purchase.
In addition, percentages are fundamental in financial education, helping to calculate interest, taxes, and other financial transactions. In the 5th grade of elementary school, students should learn to associate notable percentages such as 10%, 25%, 50%, 75%, and 100% with their corresponding fractions and to calculate these percentages of whole numbers. This knowledge is essential for developing mathematical skills and solving everyday problems efficiently.
10% (Tenth)
The concept of 10% represents a tenth of a number. In other words, when we want to calculate 10% of a number, we are dividing that number by 10. This mathematical operation is simple and straightforward, and can be performed both mentally and with the help of a calculator.
For example, if we are dealing with the number 100, to find 10% of that number, we divide 100 by 10, which results in 10. This means that 10% of 100 is 10. This concept is widely used in everyday situations, such as calculating discounts or dividing quantities equally.
Furthermore, understanding that 10% is a fraction of 1/10 is fundamental for associating percentages with fractions and vice versa. This association facilitates the understanding of other percentages and their respective fractions in the future, making the learning process progressive and interconnected.
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10% represents a tenth of a number.
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To calculate 10%, divide the number by 10.
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Example: 10% of 100 is 10.
25% (Quarter)
The concept of 25% represents a quarter of a number, that is, one fourth of the total. To calculate 25% of a number, we divide that number by 4. This method is quite intuitive and can be applied in various everyday situations.
For example, when calculating 25% of 100, we divide 100 by 4, resulting in 25. Thus, 25% of 100 is 25. This percentage is often used in contexts such as store discounts, where a quarter of the original price is subtracted.
Understanding that 25% corresponds to 1/4 helps create a solid foundation for working with other percentages. The association between fractions and percentages is an essential skill in mathematics, facilitating the resolution of more complex problems in the future.
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25% represents a quarter of a number.
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To calculate 25%, divide the number by 4.
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Example: 25% of 100 is 25.
50% (Half)
The concept of 50% represents half of a number. Calculating 50% of a number is simple: just divide the number by 2. This calculation is one of the most common and intuitive, as half is a fraction that we frequently use in various everyday situations.
For example, to find 50% of 100, we divide 100 by 2, resulting in 50. Therefore, 50% of 100 is 50. This percentage is widely used in discounts, splitting quantities, and other situations where something needs to be divided equally.
Understanding that 50% is equivalent to 1/2 helps students relate percentages to fractions. This understanding is crucial for developing advanced mathematical skills, as many future operations will depend on this foundation.
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50% represents half of a number.
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To calculate 50%, divide the number by 2.
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Example: 50% of 100 is 50.
75% (Three Quarters)
The concept of 75% represents three quarters of a number, meaning 75% is equal to 3/4 of the total. To calculate 75% of a number, we can multiply the number by 0.75 or divide by 4 and then multiply by 3. This calculation is a bit more complex, but still accessible with practice.
For example, to find 75% of 100, we can multiply 100 by 0.75, resulting in 75. Alternatively, we can divide 100 by 4 (which results in 25) and then multiply by 3, also obtaining 75. Therefore, 75% of 100 is 75. This percentage is useful in contexts like significant discounts and divisions that are not necessarily equal.
Understanding that 75% is equivalent to 3/4 helps connect percentages with fractions, strengthening the ability to work with both representations. This association is vital for effectively solving more advanced mathematical problems.
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75% represents three quarters of a number.
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To calculate 75%, multiply the number by 0.75 or divide by 4 and multiply by 3.
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Example: 75% of 100 is 75.
To Remember
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Percentage: A representation of a fraction of 100.
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Tenth: Corresponds to 10% of a number.
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Quarter: Corresponds to 25% of a number.
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Half: Corresponds to 50% of a number.
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Three Quarters: Corresponds to 75% of a number.
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Total: Corresponds to 100% of a number.
Conclusion
In the lesson about notable percentages, we discussed how to calculate and interpret the percentages of 10%, 25%, 50%, 75%, and 100%, associating them with their corresponding fractions: tenth, quarter, half, three quarters, and total. This knowledge is fundamental to understanding and applying percentages in various everyday situations, such as in discounts and divisions of quantities.
Understanding these percentages facilitates not only mathematical calculations but also the interpretation of data and information in various contexts, such as in financial education and statistics. Knowing how to calculate percentages of whole numbers helps develop practical skills that are useful in daily life and in other school subjects.
We encourage students to continue exploring the topic of percentages, as it is an essential skill for life. Understanding percentages and their practical applications contributes to a better comprehension of financial, commercial, and even scientific matters, preparing students for real and future complex situations.
Study Tips
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Practice percentage calculations with different numbers to gain fluency and confidence. Use real situations, such as calculating discounts on products or dividing quantities fairly.
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Associate percentages with fractions to facilitate understanding and calculations. For example, remember that 50% is the same as 1/2, and 25% is equal to 1/4.
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Use visual aids, such as graphs and diagrams, to represent percentages. This helps better visualize the parts of a whole and understand the relationship between different percentages.
