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Lesson Example Discussion Quiz: Class Homework

Step-5

Title: Surface area for Prism & Sphere

Grade: 6-a Lesson: S3-L3

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

Lesson Steps

Step	Type	Explanation	Answer
1	Problem	Find the total surface area of a sphere. If the diameter of a sphere is 24 in.
2	Step	The given values are	d = 24 in
3	Hint	\$"radius" = ("diameter")/2\$	⇒ \$"r" = 24/2\$ ⇒ r = 12 in
4	Formula	The total surface area of a sphere is	\$"A" = 4π("r"^2)\$
5	Step	Now plug the values in the formula	\$"A" = 4 times 3.14 times (12)^2\$
6	Step	After simplification	\$"A" = 4 times 3.14 times 144\$
7	Step	Make it simpler	A = 1808.64 sq.in
8	Step	So ,the total surface area of a sphere is 1808.64 sq.in
9	SumUp	Can you summarize what you’ve understood in the above steps?
10	Choice.A	This is wrong because it does not accurately represents the total surface area of the sphere	1880.46 sq.in
11	Choice.B	This is correct because it accurately represents the total surface area of the sphere	1808.64 sq.in
12	Choice.C	This is wrong because it does not accurately represents the total surface area of the sphere	1880.64 sq.in
13	Choice.D	This is wrong because it does not accurately represents the total surface area of the sphere	1808.46 sq.in
14	Answer	Option	B
15	SumUp	Can you summarize what you’ve understood in the above steps?

Step

Type

Explanation

Answer

Problem

Find the total surface area of a sphere. If the diameter of a sphere is 24 in.

Step

The given values are

d = 24 in

Hint

\$"radius" = ("diameter")/2\$

⇒ \$"r" = 24/2\$
⇒ r = 12 in

Formula

The total surface area of a sphere is

\$"A" = 4π("r"^2)\$

Step

Now plug the values in the formula

\$"A" = 4 times 3.14 times (12)^2\$

Step

After simplification

\$"A" = 4 times 3.14 times 144\$

Step

Make it simpler

A = 1808.64 sq.in

Step

So ,the total surface area of a sphere is 1808.64 sq.in

SumUp

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

Choice.A

This is wrong because it does not accurately represents the total surface area of the sphere

1880.46 sq.in

Choice.B

This is correct because it accurately represents the total surface area of the sphere

1808.64 sq.in

Choice.C

This is wrong because it does not accurately represents the total surface area of the sphere

1880.64 sq.in

Choice.D

This is wrong because it does not accurately represents the total surface area of the sphere

1808.46 sq.in

Answer

Option

SumUp

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