What Is 90 Of 130 Inches

What is 90% of 130 Inches? A Comprehensive Guide to Percentage Calculations

Calculating percentages is a fundamental skill with wide-ranging applications, from everyday budgeting to complex scientific calculations. Understanding how to determine a percentage of a given value is crucial for accurate estimations and informed decision-making. This article will delve into the process of calculating 90% of 130 inches, providing a step-by-step explanation, exploring different methods, and highlighting the practical applications of percentage calculations.

Understanding Percentages

Before we tackle the specific calculation, let's solidify our understanding of percentages. A percentage is a fraction or ratio expressed as a number out of 100. The symbol "%" represents "per cent" or "out of one hundred." For example, 50% means 50 out of 100, which is equivalent to 1/2 or 0.5 in decimal form.

Key Concepts:

• Percentage: A ratio or fraction expressed as a number out of 100.
• Whole Number: The total value from which the percentage is calculated (in this case, 130 inches).
• Part: The portion of the whole number that represents the calculated percentage.

Method 1: Using Decimal Conversion

This is the most straightforward method for calculating percentages. We convert the percentage to a decimal and then multiply it by the whole number.

Steps:

1. Convert the percentage to a decimal: Divide the percentage by 100. In this case, 90% / 100 = 0.90.
2. Multiply the decimal by the whole number: 0.90 * 130 inches = 117 inches.

Therefore, 90% of 130 inches is 117 inches.

Method 2: Using Fractions

Percentages can also be expressed as fractions. This method involves converting the percentage to a fraction and then performing the calculation.

Steps:

1. Convert the percentage to a fraction: 90% can be written as 90/100.
2. Simplify the fraction (if possible): 90/100 simplifies to 9/10.
3. Multiply the fraction by the whole number: (9/10) * 130 inches = 117 inches.

Again, we arrive at the answer: 90% of 130 inches is 117 inches.

Method 3: Using Proportions

This method uses the concept of proportions to solve for the unknown value.

Steps:

1. Set up a proportion: We can set up a proportion as follows: 90/100 = x/130, where 'x' represents the unknown value (90% of 130 inches).
2. Cross-multiply: Multiply 90 by 130 and 100 by x: 11700 = 100x.
3. Solve for x: Divide both sides by 100: x = 117 inches.

This method confirms that 90% of 130 inches is 117 inches.

Practical Applications of Percentage Calculations

The ability to calculate percentages has countless practical applications in various aspects of life. Here are a few examples:

1. Retail and Sales:

• Discounts: Calculating discounts on items during sales. For instance, a 20% discount on a $100 item would be $20 off.
• Taxes: Determining the amount of sales tax added to a purchase price.
• Profit Margins: Calculating the profit margin on goods sold.

2. Finance and Budgeting:

• Interest Rates: Calculating interest earned on savings accounts or interest paid on loans.
• Investment Returns: Determining the return on investment (ROI) from various investments.
• Budgeting: Allocating a percentage of income to different budget categories (e.g., housing, food, transportation).

3. Science and Engineering:

• Data Analysis: Calculating percentages in statistical analysis, such as determining the percentage of a population with a specific characteristic.
• Measurement and Conversion: Converting units of measurement, often involving percentage calculations.
• Experimentation: Calculating percentage error in scientific experiments.

4. Everyday Life:

• Tip Calculation: Calculating a tip at a restaurant.
• Recipe Adjustments: Adjusting the quantities of ingredients in a recipe.
• Grading: Calculating grades in educational settings.

Advanced Percentage Calculations: Beyond the Basics

While calculating 90% of 130 inches is a relatively simple problem, the principles involved can be applied to more complex scenarios. Here are some examples of more advanced percentage calculations:

• Calculating Percentage Increase or Decrease: Determining the percentage change between two values. For instance, if a price increases from $50 to $60, the percentage increase is 20%.
• Finding the Original Value: Determining the original value when given a percentage and the resulting value. For instance, if 75% of a number is 60, the original number is 80.
• Compound Interest Calculations: Calculating compound interest, which involves applying interest to both the principal and accumulated interest.

Mastering Percentage Calculations: Tips and Tricks

• Practice Regularly: The more you practice percentage calculations, the more comfortable you'll become.
• Use Different Methods: Experiment with different methods (decimal conversion, fractions, proportions) to find the approach that best suits your understanding.
• Check Your Work: Always double-check your calculations to ensure accuracy.
• Utilize Online Calculators: Online percentage calculators can be helpful for verifying your answers or performing more complex calculations. However, understanding the underlying principles is essential.
• Break Down Complex Problems: For complex percentage problems, break them down into smaller, manageable steps.

Conclusion: The Importance of Percentage Literacy

The ability to calculate percentages is a valuable skill with numerous practical applications. Understanding the different methods and practicing regularly will improve your proficiency and allow you to confidently tackle percentage calculations in various contexts, from everyday tasks to more complex mathematical problems. By mastering this fundamental skill, you'll enhance your problem-solving abilities and improve your overall numerical literacy. Remember that the calculation of 90% of 130 inches, as demonstrated in this article, serves as a building block to understanding and mastering more intricate percentage-based problems. The consistent application of these methods will equip you to tackle various percentage-related challenges effectively.