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Lesson Example Discussion Quiz: Class Homework

Step-5

Title: Volume of 3d-shapes(cone , cylinder)

Grade: 4-a Lesson: S3-L4

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

Lesson Steps

Step	Type	Explanation	Answer
1	Problem	The height of a cone is 18 ft, and the diameter of its base is 10 ft. Find the volume of the cone. ( π = 3.141).
2	Step	The given values are	h =18 ft and d = 10 ft ( π = 3.141)
3	Formula	The formula for the volume (V) of a cone is given by	\$V = 1/3 times π times (r^2) times h\$
4	Step	The diameter (d) is twice the radius (r)	⇒ \$r = d/2\$ ⇒ \$ r = 10/2 \$ ⇒ r = 5 ft
5	Step	Now plug the values into the formula	\$V = 1/3 times 3.141 times (5)^2 times 18\$
6	Step	Make it simpler	⇒ \$V = 1/3 times 3.141 times 450\$ ⇒ \$V = 1413.45/3\$ ⇒ V = 471.15 cu.ft
7	Step	Therefore, the volume of the cone is 471.75 cu.ft.
8	SumUp	Can you summarize what you’ve understood in the above steps?
9	Choice.A	417.51 cum.ft is not correct because it doesn’t match the calculated volume	417.51 cu.ft
10	Choice.B	417.51 cum.ft is not correct because it doesn’t match the calculated volume	471.51 cu.ft
11	Choice.C	417.51 cum.ft is not correct because it doesn’t match the calculated volume	417.15 cu.ft
12	Choice.D	471.15 cum.ft is correct because it matches the calculated by using the volume of a cone	471.15 cu.ft
13	Answer	Option	B
14	SumUp	Can you summarize what you’ve understood in the above steps?

Step

Type

Explanation

Answer

Problem

The height of a cone is 18 ft, and the diameter of its base is 10 ft. Find the volume of the cone. ( π = 3.141).

Step

The given values are

h =18 ft and d = 10 ft ( π = 3.141)

Formula

The formula for the volume (V) of a cone is given by

\$V = 1/3 times π times (r^2) times h\$

Step

The diameter (d) is twice the radius (r)

⇒ \$r = d/2\$

⇒ \$ r = 10/2 \$

⇒ r = 5 ft

Step

Now plug the values into the formula

\$V = 1/3 times 3.141 times (5)^2 times 18\$

Step

Make it simpler

⇒ \$V = 1/3 times 3.141 times 450\$

⇒ \$V = 1413.45/3\$

⇒ V = 471.15 cu.ft

Step

Therefore, the volume of the cone is 471.75 cu.ft.

SumUp

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

Choice.A

417.51 cum.ft is not correct because it doesn’t match the calculated volume

417.51 cu.ft

Choice.B

417.51 cum.ft is not correct because it doesn’t match the calculated volume

471.51 cu.ft

Choice.C

417.51 cum.ft is not correct because it doesn’t match the calculated volume

417.15 cu.ft

Choice.D

471.15 cum.ft is correct because it matches the calculated by using the volume of a cone

471.15 cu.ft

Answer

Option

SumUp

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