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Title: Surface area for Cone & Cuboid

Grade: 6-a Lesson: S3-L1

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

Lesson Steps

Step	Type	Explanation	Answer
1	Problem	Calculate the cuboid height whose lateral surface area is 616 square in and whose length and breadth are 10 in and 18 in, respectively.
2	Step	The given values are	Lateral surface area = 616 sq.in , l = 10 in and w = 18 in
3	Formula	The formula for the lateral surface area of a cuboid is:	\$"Lateral surface area" = 2 times( "length" + "breadth") times "height"\$
4	Step	Now plug the values in the formula	\$616 = 2 times(10 + 18) times h\$
5	Step	Now slove for h	⇒ \$616 = 2 times 28 "h"\$ ⇒ \$"h" = \cancel(616)^11 / \cancel(56)\$ ⇒ h = 11 in
6	Step	So, the height of the cuboid is 11 in.
7	SumUp	Can you summarize what you’ve understood in the above steps?
8	Choice.A	This is incorrect because it does not match the calculated height	17 in
9	Choice.B	This is correct because it matches the calculated height of the cuboid	11 in
10	Choice.C	This is incorrect because it does not match the calculated height	15 in
11	Choice.D	This is incorrect because it does not match the calculated height	21 in
12	Answer	Option	B
13	SumUp	Can you summarize what you’ve understood in the above steps?

Step

Type

Explanation

Answer

Problem

Calculate the cuboid height whose lateral surface area is 616 square in and whose length and breadth are 10 in and 18 in, respectively.

Step

The given values are

Lateral surface area = 616 sq.in , l = 10 in and w = 18 in

Formula

The formula for the lateral surface area of a cuboid is:

\$"Lateral surface area" = 2 times( "length" + "breadth") times "height"\$

Step

Now plug the values in the formula

\$616 = 2 times(10 + 18) times h\$

Step

Now slove for h

⇒ \$616 = 2 times 28 "h"\$
⇒ \$"h" = \cancel(616)^11 / \cancel(56)\$
⇒ h = 11 in

Step

So, the height of the cuboid is 11 in.

SumUp

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

Choice.A

This is incorrect because it does not match the calculated height

17 in

Choice.B

This is correct because it matches the calculated height of the cuboid

11 in

Choice.C

This is incorrect because it does not match the calculated height

15 in

Choice.D

This is incorrect because it does not match the calculated height

21 in

Answer

Option

SumUp

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