Complete The Chart Below Mastering Percentages And Proportions

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#Complete the chart is an essential skill in mathematics, particularly when dealing with percentages and proportions. This article will provide a comprehensive guide on how to complete such charts effectively, with detailed explanations and step-by-step solutions. We'll break down two key types of percentage problems: finding a percentage of a number and determining what percentage one number is of another. Understanding these concepts is crucial for various real-life applications, from calculating discounts and taxes to analyzing statistical data.

Understanding Percentages

In understanding percentages, it's crucial to grasp the fundamental concept that a percentage is a way of expressing a number as a fraction of 100. The term "percent" comes from the Latin "per centum," meaning "out of one hundred." This means that when we talk about a certain percentage, we're essentially referring to a part of a whole, where the whole is considered to be 100 units. For instance, if we say 50%, we mean 50 out of every 100 units. This foundational understanding is key to tackling percentage problems effectively. To illustrate, let's consider some examples. If a store offers a 20% discount, it means that for every 100 dollars, you save 20 dollars. Similarly, if a student scores 80% on a test, it means they answered 80 out of every 100 questions correctly. These examples highlight how percentages are used to represent proportions in a standardized manner, making it easier to compare different quantities. Moreover, understanding percentages involves being able to convert them into fractions and decimals, and vice versa. This flexibility is essential for solving various types of percentage problems. For example, 50% can be expressed as the fraction 1/2 or the decimal 0.5. These conversions allow us to perform mathematical operations more easily, such as calculating the actual amount of a discount or the final price after tax. In essence, mastering the concept of percentages involves not only understanding what they represent but also being able to manipulate them effectively in different forms and contexts. This skill is invaluable in numerous real-world scenarios, from personal finance to scientific analysis.

Problem 1: What is 50% of 120?

To solve the first problem, “What is 50% of 120?”, we need to find 50 percent of 120. To picture this, imagine 120 as the whole, representing 100%. We want to find the amount that corresponds to half of this whole. This is where the concept of percentages as fractions becomes particularly useful. As we've discussed, 50% is equivalent to 50 out of 100, which can be simplified to the fraction 1/2. Therefore, finding 50% of 120 is the same as finding half of 120. This visual representation helps in understanding the problem intuitively. Now, let's move on to the solving part. To find 50% of 120, we can multiply 120 by the decimal equivalent of 50%, which is 0.5. Alternatively, we can multiply 120 by the fraction 1/2. Both methods will give us the same result. Mathematically, this is expressed as: 50% of 120 = 0. 5 * 120. Performing this calculation, we get: 0. 5 * 120 = 60. Therefore, 50% of 120 is 60. This means that if we divide 120 into two equal parts, each part will be 60. Another way to solve this is by using proportions. We can set up the proportion as follows: 50/100 = x/120, where x is the value we want to find. By cross-multiplying, we get: 100x = 50 * 120. Simplifying this, we have: 100x = 6000. Dividing both sides by 100, we find: x = 60. This method also confirms that 50% of 120 is indeed 60. In conclusion, whether we use the decimal method, the fraction method, or the proportion method, the result is the same: 50% of 120 is 60. This demonstrates the versatility of percentage calculations and the importance of understanding the underlying concepts.

Picture It: 100%

To picture 100% in this context, envision 120 as the complete entity, the entirety of what we're working with. Think of it as a whole pie, a full circle, or a complete set of items. This entire entity represents 100%, which serves as our baseline for all percentage calculations related to this problem. Visualizing 100% as 120 helps in understanding that any percentage we calculate will be a portion of this whole. For instance, if we were to find 50% of 120, we would be looking for half of this entire entity. Similarly, 25% would represent a quarter, and so on. This visual anchor is crucial for developing an intuitive grasp of percentages and their relationship to the whole. To further illustrate, imagine a bar graph where the full length of the bar represents 120 units and corresponds to 100%. If we want to find 50% of 120, we would visually divide the bar into two equal parts, each representing 60 units. This visual partitioning makes it clear that 50% is exactly half of the whole. Similarly, if we were to calculate 25%, we would divide the bar into four equal parts, each representing 30 units. This visual method is particularly helpful for students who are just beginning to learn about percentages, as it provides a concrete representation of abstract concepts. Furthermore, picturing 100% as 120 allows us to create a mental benchmark for estimating the values of other percentages. For example, if we know that 100% is 120, we can easily estimate that 10% would be 12 (one-tenth of 120), and 20% would be 24 (twice 10%). This ability to estimate is a valuable skill in everyday situations, such as calculating tips or discounts. In summary, picturing 100% as 120 provides a foundational visual aid for understanding and solving percentage problems. It allows us to see the relationship between the whole and its parts, making percentage calculations more intuitive and accessible.

Solve

To solve this problem, we can use the understanding that 50% is equivalent to half of a quantity. Therefore, to find 50% of 120, we need to calculate half of 120. This can be done in several ways, each providing a clear path to the solution. One straightforward method is to divide 120 by 2. This operation directly gives us the value that represents 50% of the whole. Mathematically, this is expressed as: 120 / 2 = 60. This simple division shows that 50% of 120 is 60. Another approach involves converting the percentage into a decimal or a fraction and then multiplying it by 120. As we discussed earlier, 50% can be written as the decimal 0.5 or the fraction 1/2. Using the decimal form, we multiply 0.5 by 120: 0. 5 * 120 = 60. This method confirms our previous result, demonstrating the versatility of percentage calculations. Alternatively, we can use the fraction form. Multiplying 120 by 1/2 is the same as dividing 120 by 2, which we already know gives us 60. This fractional approach reinforces the concept that 50% is half of the whole. Furthermore, we can use the concept of proportions to solve this problem. Setting up a proportion involves creating an equation that equates two ratios. In this case, we can set up the proportion as: 50/100 = x/120, where x represents the value we are trying to find. To solve for x, we cross-multiply: 100x = 50 * 120. This simplifies to: 100x = 6000. Dividing both sides by 100, we get: x = 60. This proportional method provides yet another way to verify that 50% of 120 is 60. In conclusion, whether we use division, decimal multiplication, fractional multiplication, or proportions, the solution remains consistent: 50% of 120 is 60. This consistency highlights the fundamental nature of percentage calculations and the interconnectedness of different mathematical approaches.

Problem 2: 15 is what percent of 60?

Moving on to the second problem, “15 is what percent of 60?”, this question shifts our focus from finding a percentage of a number to determining the percentage that one number represents of another. In this scenario, 15 is the part, and 60 is the whole. The goal is to express 15 as a percentage of 60. This type of problem is common in various real-life situations, such as calculating a test score as a percentage or determining the percentage increase or decrease in a quantity. To picture this problem, imagine 60 as the entire pie, representing 100%. The question then becomes: what slice of this pie does 15 represent? This visual representation helps in understanding the proportional relationship between 15 and 60. To solve this, we first need to create a fraction that represents the relationship between 15 and 60. This fraction is 15/60. This fraction tells us what proportion of 60 is represented by 15. To convert this fraction into a percentage, we need to multiply it by 100. This is because a percentage is essentially a fraction expressed out of 100. Therefore, the calculation becomes: (15/60) * 100. Simplifying the fraction 15/60, we can divide both the numerator and the denominator by their greatest common divisor, which is 15. This gives us the simplified fraction 1/4. Now, we can multiply this simplified fraction by 100: (1/4) * 100 = 25. This means that 15 is 25% of 60. Another way to approach this problem is by setting up a proportion. We can express the problem as: 15/60 = x/100, where x represents the percentage we are trying to find. To solve for x, we can cross-multiply: 60x = 15 * 100. This simplifies to: 60x = 1500. Dividing both sides by 60, we get: x = 25. This proportional method confirms that 15 is indeed 25% of 60. In conclusion, whether we use the fraction method or the proportion method, the result is the same: 15 is 25% of 60. This demonstrates the importance of understanding the relationship between parts and wholes when dealing with percentages.

Picture It: 100%

To picture 100% in the context of the problem