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2/19/2023
Maths
Finding the Circumference and Area of a Circle Revision Note
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.
2/19/2023
674
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.
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 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.
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 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.
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 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.
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 3.14: Diameter = 20 รท 3.14 = 6.37 cm
Highlight: The final answer is 6.4 cmยฒ
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.
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 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
This example introduces the formula for calculating the area of a circle and demonstrates how to square the radius in the calculation.
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 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
This example reinforces the application of the area formula for circles and provides additional practice in squaring the radius and performing the calculation.
17
1403
10th
Parts of a circle, area & circumference
This is a finished and completed worksheet that applies very helpful information for the subject.
5
329
10th
Area & circumference formulas
This is a finished and completed worksheet that applies very helpful information for the subject.
0
472
10th
quiz 10-3 angles, arcs, and segment lengths formed by intersecting chords, secants, and rangers
old work
1
247
9th
Properties of Parallelograms
This is properties of parrallelograms with examples.
0
121
10th
Inscribed Quadrulaterals
This is a finished and completed worksheet that applies very helpful information for the subject.
24
1877
10th
10:4 Inscribed Angles
This is a finished and completed worksheet that applies very helpful information for the subject.
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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
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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.
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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 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.
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Improve your grades
Join milions of students
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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 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.
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Improve your grades
Join milions of students
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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 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.
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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 3.14: Diameter = 20 รท 3.14 = 6.37 cm
Highlight: The final answer is 6.4 cmยฒ
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.
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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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 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
This example introduces the formula for calculating the area of a circle and demonstrates how to square the radius in the calculation.
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Join milions of students
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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 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
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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Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
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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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
I think itโs very much worth it and youโll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still donโt get it!!! In the end I think itโs worth it ๐๐ โ ๏ธAlso DID I MENTION ITS FREEE YOU DONโT HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLYโ๏ธโ๏ธโ ๏ธ
Thomas R
iOS user
Knowunity is the BEST app Iโve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help๐ค๐ค
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.๐๐ฉท๐
Marco B
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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as Iโve seen! Geometry too!
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
I think itโs very much worth it and youโll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still donโt get it!!! In the end I think itโs worth it ๐๐ โ ๏ธAlso DID I MENTION ITS FREEE YOU DONโT HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLYโ๏ธโ๏ธโ ๏ธ
Thomas R
iOS user
Knowunity is the BEST app Iโve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades
Brad T
Android user
Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help๐ค๐ค
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
I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend
Aubrey
iOS user
Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.๐๐ฉท๐
Marco B
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 ๐๐๐ฒ๐ค๐โจ๐๐ฎ
Elisha
iOS user
This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as Iโve seen! Geometry too!
Paul T
iOS user
