We are open Saturday and Sunday!

Call Now to Set Up Tutoring:

(888) 888-0446

Basic Geometry : How to find the ratio of diameter and circumference

Study concepts, example questions & explanations for Basic Geometry

Create An Account

All Basic Geometry Resources

9 Diagnostic Tests 164 Practice Tests Question of the Day Flashcards Learn by Concept

Example Questions

Example Question #1 : How To Find The Ratio Of Diameter And Circumference

Let represent the area of a circle and represent its circumference. Which of the following equations expresses in terms of ?

Possible Answers:

C^2

Correct answer:

Explanation:

The formula for the area of a circle is $A=\pi r^2$ , and the formula for circumference is $C=2\pi r$ . If we solve for C in terms of r, we get
$r=C/2\pi$ .

We can then substitute this value of r into the formula for the area:

$A=\pi r^2$

$=\pi (C/2\pi )^2$

$=C^2\pi /4\pi ^2$

$=C^2/4\pi$

Report an Error

Example Question #371 : Basic Geometry

A can of soup has a base area of $16\pi$ . What is the ratio of the can's diameter to its circumference?

Possible Answers:

$\frac{\pi}{1}$

$\frac{1}{2\pi}$

$\frac{2\pi}{1}$

$\frac{\pi}{8}$

$\frac{1}{\pi}$

Correct answer:

$\frac{1}{\pi}$

Explanation:

If the cirlcle has an area of $16\pi$ then we need to find a way to determine the diameter of the circle. We must do 4 things:

1. Find the radius of the circle since all we know is the area of the circle.

2. Double the radius to find the diameter.

3. Find the circumference by $C=\pi d$

4. Write the ratio

$A_{circle}=\pi r^2$

$16\pi=\pi r^2$

Solving to find the radius we get:

16=r^2

4=r

So if the radius is 4 then the diameter is:

d=2(4)=8

Then the circumference is:

$C=8\pi$

The ratio of the diameter to the circumference is:

$\frac{d}{C}=\frac{8}{8\pi}=\frac{1}{\pi}$

Report an Error

Example Question #372 : Basic Geometry

The circumference of the base of a silo is $144\pi$ ft. What is the ratio of the silo's circumference to its diameter?

Possible Answers:

$\pi:1$

$144:\pi$

$1:\pi$

144:1

1:144

Correct answer:

$\pi:1$

Explanation:

Since the silo has base circumference of $144\pi$ , then according to the formula for the circumference of a circle:

$C=\pi d$

$144\pi=\pi d$

Solving for diameter:

144=d

So the diameter is 144 ft. Therefore the ratio of the circumference to the diameter would be:

$144\pi:144\rightarrow \pi:1$

Report an Error

Example Question #373 : Basic Geometry

The diameter of a certain circle is tripled. Compared to the circumference of the original circle, how many times as large is the circumference of the new circle?

Possible Answers:

$9\pi$

$3\pi$

Correct answer:

Explanation:

The easiest way to find our answer is to try actual values. Imagine we have a circle with a diameter of . Given the formula for circumference

$C=d\pi$

our circumference is simply $2\pi$ . Tripling the diameter gives a new diameter of and therefore a new circumference of $6\pi$ . We can then determine the ratio between the two circumferences.

$\frac{6\pi}{2\pi}=3$

Therefore, the new circumference is 3 times as large as the old.

Report an Error

Example Question #1 : How To Find The Ratio Of Diameter And Circumference

Find the ratio of the diameter to the circumference in a circle with radius r.

Possible Answers:

$\frac{1}{\pi}$

$2\pi{r}$

$\pi$

Correct answer:

$\frac{1}{\pi}$

Explanation:

To find a ratio, simply divide your two quantities. Remember,

D=2r

$C=2\pi{r}$

Thus,

$ratio=\frac{D}{C}=\frac{2r}{2\pi{r}}=\frac{1}{\pi}$

Report an Error

Example Question #1 : How To Find The Ratio Of Diameter And Circumference

What is the circumference to diameter ratio of a circle with a diameter of 15?

Possible Answers:

Cannot be determined.

3.75

4.14

4.75

3.14

Correct answer:

3.14

Explanation:

First you must find the circumference of a circle with a diameter of 15 with the formula $C=\pi*D$ .

$C=\pi*15=47.1$

Since the ratio of C to D is represented by $\pi=\frac{C}{D}$ , all of the ratios of Circumference to Diameter should approximately equal $\pi$ .

$\frac{47.1}{15}=3.14$

Report an Error

Example Question #372 : Basic Geometry

In the game of Sumo, both wrestlers are placed on the outer edge of the ring, on opposite sides of each other. If the wrestling ring is a perfect circle and has an area of $804.25\;ft^2$ , what would be the distance between both wrestlers?

Possible Answers:

$64\;ft$

$56\;ft$

$16\;ft$

$32\;ft$

$256\;ft$

Correct answer:

$32\;ft$

Explanation:

With the two wrestlers standing opposite each other on the edge of the ring, the distance between them would constitute the diameter of the circle. We can use the formula for circular area to find the diameter:

$\\area=\pi\cdot r^2\\ \\804.25\;ft^2=3.14159\cdot r^2\\ \\r^2=\frac{804.25\;ft^2}{3.14159}=256\;ft^2\\ \\radius=\sqrt{256\;ft^2}=16\;ft\\ \\diameter=2\cdot16\;ft=32\;ft$

Report an Error

Example Question #372 : Plane Geometry

True or false: A circle with radius 1 has circumference less than 4.

Possible Answers:

False

True

Correct answer:

False

Explanation:

The circumference of a circle is equal to its radius multiplied by $2 \pi$ , so, if the radius of a circle is 1, its circumference is

$1 \times 2 \pi = 2\pi \approx 2 \cdot 3.14 \approx 6.28$

This is greater than 4.

Report an Error

View Tutors

Clay
Certified Tutor

Grand Canyon University, Bachelor in Arts, History.

View Tutors

Michele
Certified Tutor

Georgian Court University, Bachelor in Arts, English. Georgian Court University, Master of Arts, Elementary and Middle School...

View Tutors

Sophia
Certified Tutor

Universidad del Azuay, Bachelor in Arts, International Relations.

All Basic Geometry Resources

9 Diagnostic Tests 164 Practice Tests Question of the Day Flashcards Learn by Concept

Popular Subjects

GMAT Tutors in New York City, Statistics Tutors in Philadelphia, ACT Tutors in San Diego, Biology Tutors in Philadelphia, Algebra Tutors in Los Angeles, French Tutors in San Francisco-Bay Area, Spanish Tutors in Phoenix, GRE Tutors in Miami, Spanish Tutors in Chicago, SAT Tutors in Dallas Fort Worth

Popular Courses & Classes

MCAT Courses & Classes in Denver, LSAT Courses & Classes in Atlanta, GMAT Courses & Classes in San Diego, GRE Courses & Classes in Denver, GMAT Courses & Classes in Atlanta, GRE Courses & Classes in Phoenix, MCAT Courses & Classes in Seattle, ISEE Courses & Classes in Boston, ISEE Courses & Classes in Phoenix, ACT Courses & Classes in Atlanta

Popular Test Prep

GRE Test Prep in Denver, ACT Test Prep in Atlanta, MCAT Test Prep in Denver, MCAT Test Prep in Los Angeles, LSAT Test Prep in Atlanta, GMAT Test Prep in San Diego, ISEE Test Prep in Dallas Fort Worth, GRE Test Prep in Phoenix, SAT Test Prep in Los Angeles, GMAT Test Prep in Atlanta

DMCA Complaint

If you believe that content available by means of the Website (as defined in our Terms of Service) infringes one or more of your copyrights, please notify us by providing a written notice (“Infringement Notice”) containing the information described below to the designated agent listed below. If Varsity Tutors takes action in response to an Infringement Notice, it will make a good faith attempt to contact the party that made such content available by means of the most recent email address, if any, provided by such party to Varsity Tutors.

Your Infringement Notice may be forwarded to the party that made the content available or to third parties such as ChillingEffects.org.

Please be advised that you will be liable for damages (including costs and attorneys’ fees) if you materially misrepresent that a product or activity is infringing your copyrights. Thus, if you are not sure content located on or linked-to by the Website infringes your copyright, you should consider first contacting an attorney.

Please follow these steps to file a notice:

You must include the following:

A physical or electronic signature of the copyright owner or a person authorized to act on their behalf; An identification of the copyright claimed to have been infringed; A description of the nature and exact location of the content that you claim to infringe your copyright, in \ sufficient detail to permit Varsity Tutors to find and positively identify that content; for example we require a link to the specific question (not just the name of the question) that contains the content and a description of which specific portion of the question – an image, a link, the text, etc – your complaint refers to; Your name, address, telephone number and email address; and A statement by you: (a) that you believe in good faith that the use of the content that you claim to infringe your copyright is not authorized by law, or by the copyright owner or such owner’s agent; (b) that all of the information contained in your Infringement Notice is accurate, and (c) under penalty of perjury, that you are either the copyright owner or a person authorized to act on their behalf.

Send your complaint to our designated agent at:

Charles Cohn Varsity Tutors LLC
101 S. Hanley Rd, Suite 300
St. Louis, MO 63105

Or fill out the form below:

Do not fill in this field

Contact Information

* Full legal name

Company name

* Phone number

* Email address

Address

* Address1

Address2

* City

* State

* Zipcode

* Country

Complaint Details

* URL of copyrighted work (where your original material is located)

* Please describe the copyrighted work so that it may be easily identified

I am the owner, or an agent authorized to act on behalf of the owner of an exclusive right that is allegedly infringed.

I have a good faith belief that the use of the material in the manner complained of is not authorized by the copyright owner, its agent, or the law.

This notification is accurate.

I acknowledge that there may be adverse legal consequences for making false or bad faith allegations of copyright infringement by using this process.

* Signature (your digital signature is legally binding)

HIGH SCHOOL

GRADUATE SCHOOL

K-8

Search 50+ Tests

math tutoring

science tutoring

foreign languages

elementary tutoring

other

Search 350+ Subjects

Basic Geometry : How to find the ratio of diameter and circumference

Study concepts, example questions & explanations for Basic Geometry

All Basic Geometry Resources

Example Questions

Example Question #1 : How To Find The Ratio Of Diameter And Circumference

Example Question #371 : Basic Geometry

Example Question #372 : Basic Geometry

Example Question #373 : Basic Geometry

Example Question #1 : How To Find The Ratio Of Diameter And Circumference

Example Question #1 : How To Find The Ratio Of Diameter And Circumference

Example Question #372 : Basic Geometry

Example Question #372 : Plane Geometry

All Basic Geometry Resources

Report an issue with this question

DMCA Complaint

Contact Information

Address

Complaint Details

Email address:
Your name:
Feedback: