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Lesson Example Discussion Quiz: Class Homework

Lesson

Title: Surface area for Cone & Cuboid

Grade: 6-a Lesson: S3-L1

Explanation: Hello students, let us learn a new topic in geometry today with definitions, concepts, examples, and worksheets included.

Lesson:

Definition: Surface area of Cube

The surface area of a cone is the total area of its outer surface, including the curved surface (lateral surface) and the base.
The formula for calculating the surface area of a cone is given by:
A = πr(r + l)
Where A is the surface area of the cone,r is the radius of the base of the cone, and l is the slant height of the cone.

$1$

Explanation: A cone with a height of 12 cm and a base radius of 5 cm has a slant height of 13 cm, which can be found using the Pythagorean theorem \$"l" = sqrt("r"^2 + "h"^2)\$.

Definition: Surface area of Cuboid

A cuboid is a three-dimensional rectangular solid with six faces, each of which is a rectangle.
The surface area of a cuboid is the sum of the areas of all its faces.
To calculate the surface area (SA) of a cuboid, use the formula:
SA = 2lw + 2lh + 2hw, where l is the length of the cuboid, w is its width, and h is its height.

$2$

Explanation: The cuboid has a length of 4 units, a width of 2 units, and a height of 3 units. Its surface area is 44 sq.units.