SaiBook.us Geometry

Home Course Section

Schedule Admission Social

Lesson Example Discussion Quiz: Class Homework

Step-4

Title: Circumference of a Circle

Grade: 4-a Lesson: S2-L4

Explanation: Hello Students, time to practice and review the steps for the problem.

Lesson Steps

Step	Type	Explanation	Answer
1	Problem	A circle having an area of 441 square meters , find the circumference of a circle.
2	Step	Area of a circle is given	441 sq.meters
3	Formula	The circumference of a circle is	C = \$2 \times π \times ((\sqrt area) / π)\$ (π = 3.1415)
4	Step	Substitute the value in the formula	C = \$2 \times π \times ((\sqrt 441) /π)\$
5	Step	After simplification	C = \$ 2 \times π \times 11.85\$
6	Step	After simplification	C = 74.45 m
7	Step	The circumference of a circle is C = 74.45 m.
8	SumUp	Can you summarize what you’ve understood in the above steps?
9	Choice.A	This is not the correct answer because it is slightly less accurate when rounded to two decimal places compared to option B	74.40 m
10	Choice.B	This is the correct answer because it corresponds to the calculated circumference	74.45 m
11	Choice.C	This is not the correct answer because it is slightly less accurate when rounded to two decimal places compared to option B	74.38 m
12	Choice.D	This is not the correct answer because it is slightly less accurate when rounded to two decimal places compared to option B	74.24 m
13	Answer	Option	B
14	SumUp	Can you summarize what you’ve understood in the above steps?

Step

Type

Explanation

Answer

Problem

A circle having an area of 441 square meters , find the circumference of a circle.

Step

Area of a circle is given

441 sq.meters

Formula

The circumference of a circle is

C = \$2 \times π \times ((\sqrt area) / π)\$

(π = 3.1415)

Step

Substitute the value in the formula

C = \$2 \times π \times ((\sqrt 441) /π)\$

Step

After simplification

C = \$ 2 \times π \times 11.85\$

Step

After simplification

C = 74.45 m

Step

The circumference of a circle is C = 74.45 m.

SumUp

Can you summarize what you’ve understood in the above steps?

Choice.A

This is not the correct answer because it is slightly less accurate when rounded to two decimal places compared to option B

74.40 m

Choice.B

This is the correct answer because it corresponds to the calculated circumference

74.45 m

Choice.C

This is not the correct answer because it is slightly less accurate when rounded to two decimal places compared to option B

74.38 m

Choice.D

This is not the correct answer because it is slightly less accurate when rounded to two decimal places compared to option B

74.24 m

Answer

Option

SumUp

Can you summarize what you’ve understood in the above steps?