What Number Is $21.5 %$ Smaller Than 72?Give Your Answer As A Decimal.

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Introduction

In this article, we will explore the concept of percentage decrease and how to calculate the number that is a certain percentage smaller than a given value. We will use the example of finding the number that is $21.5 %$ smaller than 72 and provide the answer as a decimal.

Understanding Percentage Decrease

Percentage decrease is a way to express a reduction in value as a percentage of the original value. It is calculated by finding the difference between the original value and the new value, dividing by the original value, and then multiplying by 100 to get the percentage decrease.

For example, if we have a value of 100 and it decreases to 80, the percentage decrease is:

100−80100×100=20%\frac{100 - 80}{100} \times 100 = 20 \%

This means that the value has decreased by 20%.

Calculating the Number that is $21.5 %$ Smaller than 72

To calculate the number that is $21.5 %$ smaller than 72, we need to find the difference between 72 and the new value, divide by 72, and then multiply by 100 to get the percentage decrease.

Let's call the new value x. We can set up the equation:

72−x72×100=21.5%\frac{72 - x}{72} \times 100 = 21.5 \%

To solve for x, we can start by dividing both sides of the equation by 100:

72−x72=0.215\frac{72 - x}{72} = 0.215

Next, we can multiply both sides of the equation by 72 to get rid of the fraction:

72−x=15.4872 - x = 15.48

Now, we can solve for x by subtracting 72 from both sides of the equation:

−x=−56.52-x = -56.52

Finally, we can multiply both sides of the equation by -1 to get the value of x:

x=56.52x = 56.52

Conclusion

In this article, we calculated the number that is $21.5 %$ smaller than 72 and provided the answer as a decimal. We used the concept of percentage decrease to find the difference between the original value and the new value, and then solved for the new value using algebra.

Calculating Percentage Decrease in Real-World Scenarios

Percentage decrease is a useful concept in many real-world scenarios, such as:

  • Finance: When a stock price decreases by a certain percentage, it can affect the value of an investment.
  • Business: When a company's sales decrease by a certain percentage, it can impact the company's revenue and profitability.
  • Science: When a physical quantity decreases by a certain percentage, it can affect the behavior of a system.

Tips for Calculating Percentage Decrease

Here are some tips for calculating percentage decrease:

  • Use a calculator: When calculating percentage decrease, it's often easier to use a calculator to avoid errors.
  • Check your units: Make sure that your units are consistent when calculating percentage decrease.
  • Use a formula: The formula for percentage decrease is:

Original Value−New ValueOriginal Value×100\frac{Original\ Value - New\ Value}{Original\ Value} \times 100

Common Mistakes when Calculating Percentage Decrease

Here are some common mistakes to avoid when calculating percentage decrease:

  • Not checking units: Make sure that your units are consistent when calculating percentage decrease.
  • Not using a formula: Using a formula can help you avoid errors when calculating percentage decrease.
  • Not rounding correctly: When rounding numbers, make sure to round to the correct number of decimal places.

Conclusion

In this article, we explored the concept of percentage decrease and how to calculate the number that is a certain percentage smaller than a given value. We used the example of finding the number that is $21.5 %$ smaller than 72 and provided the answer as a decimal. We also discussed real-world scenarios where percentage decrease is useful and provided tips for calculating percentage decrease.

Introduction

In our previous article, we explored the concept of percentage decrease and how to calculate the number that is a certain percentage smaller than a given value. In this article, we will answer some frequently asked questions about percentage decrease.

Q&A

Q: What is percentage decrease?

A: Percentage decrease is a way to express a reduction in value as a percentage of the original value.

Q: How do I calculate percentage decrease?

A: To calculate percentage decrease, you need to find the difference between the original value and the new value, divide by the original value, and then multiply by 100.

Q: What is the formula for percentage decrease?

A: The formula for percentage decrease is:

Original Value−New ValueOriginal Value×100\frac{Original\ Value - New\ Value}{Original\ Value} \times 100

Q: How do I calculate the number that is a certain percentage smaller than a given value?

A: To calculate the number that is a certain percentage smaller than a given value, you need to find the difference between the original value and the new value, divide by the original value, and then multiply by 100. You can then subtract the result from the original value to get the new value.

Q: What is the difference between percentage decrease and percentage increase?

A: Percentage decrease is a reduction in value, while percentage increase is an increase in value. The formula for percentage increase is the same as the formula for percentage decrease, but the result is positive instead of negative.

Q: How do I calculate percentage decrease in a real-world scenario?

A: To calculate percentage decrease in a real-world scenario, you need to identify the original value and the new value, and then use the formula for percentage decrease to calculate the percentage decrease.

Q: What are some common mistakes to avoid when calculating percentage decrease?

A: Some common mistakes to avoid when calculating percentage decrease include not checking units, not using a formula, and not rounding correctly.

Q: How do I round numbers when calculating percentage decrease?

A: When rounding numbers when calculating percentage decrease, you should round to the correct number of decimal places.

Q: Can I use a calculator to calculate percentage decrease?

A: Yes, you can use a calculator to calculate percentage decrease. This can help you avoid errors and make the calculation easier.

Q: What are some real-world scenarios where percentage decrease is useful?

A: Some real-world scenarios where percentage decrease is useful include finance, business, and science.

Q: How do I apply percentage decrease in finance?

A: In finance, percentage decrease can be used to calculate the impact of a stock price decrease on an investment.

Q: How do I apply percentage decrease in business?

A: In business, percentage decrease can be used to calculate the impact of a sales decrease on revenue and profitability.

Q: How do I apply percentage decrease in science?

A: In science, percentage decrease can be used to calculate the impact of a physical quantity decrease on the behavior of a system.

Conclusion

In this article, we answered some frequently asked questions about percentage decrease. We covered topics such as calculating percentage decrease, real-world scenarios, and common mistakes to avoid. We hope that this article has been helpful in understanding percentage decrease and how to apply it in different scenarios.

Additional Resources

If you want to learn more about percentage decrease, here are some additional resources:

  • Online calculators: There are many online calculators available that can help you calculate percentage decrease.
  • Math textbooks: Math textbooks often cover percentage decrease and provide examples and exercises to help you practice.
  • Online tutorials: Online tutorials can provide step-by-step instructions on how to calculate percentage decrease.

Conclusion

In conclusion, percentage decrease is an important concept in mathematics that can be applied in many real-world scenarios. By understanding how to calculate percentage decrease and avoiding common mistakes, you can make informed decisions and solve problems more effectively.