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Easy Circle Tricks: How to Find Circumference, Diameter, and Radius

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19/02/2023

Maths

Finding the Circumference and Area of a Circle Revision Note

Easy Circle Tricks: How to Find Circumference, Diameter, and Radius

This guide explains key concepts and calculations related to circles, focusing on how to find the circumference of a circle, how to find the area of a circle, and how to find the radius of a circle. It covers essential formulas and provides step-by-step examples for various circle-related calculations.

...

19/02/2023

674

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

View

Visual Representation of Circle Components

This page provides visual representations of the key components of a circle:

The radius is clearly illustrated as a line segment extending from the center of the circle to its edge. This visual aid helps students understand that the radius is always half the length of the diameter.

The diameter is depicted as a line segment that spans the entire width of the circle, passing through its center. This illustration emphasizes that the diameter is twice the length of the radius.

Highlight: The diameter is always twice the length of the radius in any circle.

These visual representations are crucial for students to grasp the spatial relationships between different parts of a circle, which is fundamental for solving more complex geometric problems involving circles.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

View

Calculating Circumference: Example 1

This page demonstrates how to find the circumference of a circle using a given diameter:

The problem presents a circle with a diameter of 25 cm. To calculate the circumference, we use the formula:

Circumference = ฯ€ ร— diameter

Example: Using ฯ€ โ‰ˆ 3.14 and diameter = 25 cm: Circumference = 3.14 ร— 25 = 78.5 cm

Highlight: The answer may need to be expressed in cmยฒ, resulting in 78.5 cmยฒ.

This example illustrates the straightforward application of the circumference formula when the diameter is known. It also reminds students to pay attention to units in their final answer.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

View

Calculating Circumference: Example 2

This page provides another example of how to calculate the circumference of a circle, reinforcing the concept:

The problem presents a circle with a diameter of 34 cm. Using the same formula as before:

Circumference = ฯ€ ร— diameter

Example: With ฯ€ โ‰ˆ 3.14 and diameter = 34 cm: Circumference = 3.14 ร— 34 = 106.76 cm

Highlight: The answer is rounded to one decimal place: 106.8 cm

This example not only reinforces the application of the circumference formula but also introduces the concept of rounding in mathematical calculations, an important skill in practical problem-solving.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

View

Finding Diameter from Circumference: Example 1

This page demonstrates how to find the diameter of a circle when given its circumference:

The problem presents a circle with a circumference of 35 cm. To find the diameter, we rearrange the circumference formula:

Diameter = Circumference รท ฯ€

Example: With circumference = 35 cm and ฯ€ โ‰ˆ 3.14: Diameter = 35 รท 3.14 = 11.15 cm

Highlight: The answer may need to be expressed to one decimal place in cmยฒ, resulting in 11.1 cmยฒ.

This example illustrates how to manipulate the circumference formula to solve for diameter, an important skill in geometric problem-solving.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

View

Finding Diameter from Circumference: Example 2

This page provides another example of how to calculate the diameter of a circle from its circumference:

The problem presents a circle with a circumference of 20 cm. Using the rearranged formula:

Diameter = Circumference รท ฯ€

Example: With circumference = 20 cm and ฯ€ โ‰ˆ 3.14: Diameter = 20 รท 3.14 = 6.37 cm

Highlight: The final answer is 6.4 cmยฒ toonedecimalplaceto one decimal place

This example reinforces the process of finding the diameter from the circumference and emphasizes the importance of rounding and using correct units in the final answer.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

View

Calculating Area Using Radius: Example 1

This page demonstrates how to find the area of a circle using its radius:

The problem presents a circle with a radius of 15 cm. To calculate the area, we use the formula:

Area = ฯ€ ร— radiusยฒ

Example: With ฯ€ โ‰ˆ 3.14 and radius = 15 cm: Area = 3.14 ร— 15ยฒ = 3.14 ร— 225 = 706.5 cmยฒ

Highlight: The final answer is 706.5 cmยฒ toonedecimalplaceto one decimal place

This example introduces the formula for calculating the area of a circle and demonstrates how to square the radius in the calculation.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

View

Calculating Area Using Radius: Example 2

This page provides another example of how to calculate the area of a circle using its radius:

The problem presents a circle with a radius of 7 cm. Using the same formula as before:

Area = ฯ€ ร— radiusยฒ

Example: With ฯ€ โ‰ˆ 3.14 and radius = 7 cm: Area = 3.14 ร— 7ยฒ = 3.14 ร— 49 = 153.9 cmยฒ

Highlight: The final answer is 153.9 cmยฒ toonedecimalplaceto one decimal place

This example reinforces the application of the area formula for circles and provides additional practice in squaring the radius and performing the calculation.

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19 Feb 2023

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8 pages

Easy Circle Tricks: How to Find Circumference, Diameter, and Radius

This guide explains key concepts and calculations related to circles, focusing on how to find the circumference of a circle, how to find the area of a circle, and how to find the radius of a circle.... Show more

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

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Join milions of students

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Visual Representation of Circle Components

This page provides visual representations of the key components of a circle:

The radius is clearly illustrated as a line segment extending from the center of the circle to its edge. This visual aid helps students understand that the radius is always half the length of the diameter.

The diameter is depicted as a line segment that spans the entire width of the circle, passing through its center. This illustration emphasizes that the diameter is twice the length of the radius.

Highlight: The diameter is always twice the length of the radius in any circle.

These visual representations are crucial for students to grasp the spatial relationships between different parts of a circle, which is fundamental for solving more complex geometric problems involving circles.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Calculating Circumference: Example 1

This page demonstrates how to find the circumference of a circle using a given diameter:

The problem presents a circle with a diameter of 25 cm. To calculate the circumference, we use the formula:

Circumference = ฯ€ ร— diameter

Example: Using ฯ€ โ‰ˆ 3.14 and diameter = 25 cm: Circumference = 3.14 ร— 25 = 78.5 cm

Highlight: The answer may need to be expressed in cmยฒ, resulting in 78.5 cmยฒ.

This example illustrates the straightforward application of the circumference formula when the diameter is known. It also reminds students to pay attention to units in their final answer.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Calculating Circumference: Example 2

This page provides another example of how to calculate the circumference of a circle, reinforcing the concept:

The problem presents a circle with a diameter of 34 cm. Using the same formula as before:

Circumference = ฯ€ ร— diameter

Example: With ฯ€ โ‰ˆ 3.14 and diameter = 34 cm: Circumference = 3.14 ร— 34 = 106.76 cm

Highlight: The answer is rounded to one decimal place: 106.8 cm

This example not only reinforces the application of the circumference formula but also introduces the concept of rounding in mathematical calculations, an important skill in practical problem-solving.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Finding Diameter from Circumference: Example 1

This page demonstrates how to find the diameter of a circle when given its circumference:

The problem presents a circle with a circumference of 35 cm. To find the diameter, we rearrange the circumference formula:

Diameter = Circumference รท ฯ€

Example: With circumference = 35 cm and ฯ€ โ‰ˆ 3.14: Diameter = 35 รท 3.14 = 11.15 cm

Highlight: The answer may need to be expressed to one decimal place in cmยฒ, resulting in 11.1 cmยฒ.

This example illustrates how to manipulate the circumference formula to solve for diameter, an important skill in geometric problem-solving.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Finding Diameter from Circumference: Example 2

This page provides another example of how to calculate the diameter of a circle from its circumference:

The problem presents a circle with a circumference of 20 cm. Using the rearranged formula:

Diameter = Circumference รท ฯ€

Example: With circumference = 20 cm and ฯ€ โ‰ˆ 3.14: Diameter = 20 รท 3.14 = 6.37 cm

Highlight: The final answer is 6.4 cmยฒ toonedecimalplaceto one decimal place

This example reinforces the process of finding the diameter from the circumference and emphasizes the importance of rounding and using correct units in the final answer.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Calculating Area Using Radius: Example 1

This page demonstrates how to find the area of a circle using its radius:

The problem presents a circle with a radius of 15 cm. To calculate the area, we use the formula:

Area = ฯ€ ร— radiusยฒ

Example: With ฯ€ โ‰ˆ 3.14 and radius = 15 cm: Area = 3.14 ร— 15ยฒ = 3.14 ร— 225 = 706.5 cmยฒ

Highlight: The final answer is 706.5 cmยฒ toonedecimalplaceto one decimal place

This example introduces the formula for calculating the area of a circle and demonstrates how to square the radius in the calculation.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Calculating Area Using Radius: Example 2

This page provides another example of how to calculate the area of a circle using its radius:

The problem presents a circle with a radius of 7 cm. Using the same formula as before:

Area = ฯ€ ร— radiusยฒ

Example: With ฯ€ โ‰ˆ 3.14 and radius = 7 cm: Area = 3.14 ร— 7ยฒ = 3.14 ร— 49 = 153.9 cmยฒ

Highlight: The final answer is 153.9 cmยฒ toonedecimalplaceto one decimal place

This example reinforces the application of the area formula for circles and provides additional practice in squaring the radius and performing the calculation.

Circumference ~ยป The perimeter of
thr circle / distance around the
circle
Radius ~ The line that starts from
the edge of a circle to its mid

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Understanding Circle Basics

This page introduces the fundamental concepts related to circles:

Circumference is defined as the perimeter or distance around a circle. It's a crucial measurement in many geometric calculations.

Radius is described as the line segment that extends from the edge of a circle to its midpoint or center. It's half the length of the diameter.

Diameter is explained as the line segment that passes through the center of the circle, connecting two points on the circumference. It's twice the length of the radius.

Vocabulary: Circumference - The distance around a circle Vocabulary: Radius - The distance from the center to the edge of a circle Vocabulary: Diameter - The distance across a circle through its center

The page also includes simple diagrams illustrating these concepts, helping students visualize the relationships between these elements of a circle.

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This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.

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very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.

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This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now

Paul T

iOS user

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

Best app on earth! no words because itโ€™s too good

Thomas R

iOS user

Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.

Basil

Android user

This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.

Rohan U

Android user

I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didnโ€™t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as Iโ€™m sure you too will see developments.

Xander S

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH ๐Ÿ˜๐Ÿ˜๐Ÿ˜ฒ๐Ÿค‘๐Ÿ’—โœจ๐ŸŽ€๐Ÿ˜ฎ

Elisha

iOS user

This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now

Paul T

iOS user