7th Grade Math

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Volume

PART A BCDE F

Multi-Part

Lesson 1

Addresses

GLE 0706.4.3.

Lesson 1E Volume 571

Volume of Pyramids

SAND SCULPTURE Dion is

helping his brother build a sand

sculpture at the beach in the shape of

a pyramid. The square pyramid has a

base with a length and width of 12

inches each and a height of 12 inches.

1. What is the area of the base?


2. What is the volume of a square
   prism with the same dimensions as the pyramid?

A pyramid is a three-dimensional figure with one base and triangular

lateral faces, or any flat surfaces that are not bases. The lateral edges

meet at one vertex. The height of a pyramid is the distance from the

vertex perpendicular to the base.

Volume of a Pyramid

Words The volume V of a pyramid

is one third the area of the

base B times the height of

the pyramid h.

Model

h

Symbols V = _^13 Bh #

Find the Volume of a Pyramid

Find the volume of the pyramid. Round to the nearest tenth.

V = _^1

3

Bh Volume of a pyramid 2.8 in.

1.4 in.

3.2 in.

V = _^1

3

(3.2 · 1.4)2.8 B = 3.2 · 1.4, h = 2.8

V ≈ 4.2 Simplify.

The volume is about 4.2 cubic inches.

a. Find the volume of a pyramid that has a height of 9 centimeters

and a rectangular base with a length of 7 centimeters and a

width of 3 centimeters.

helpin

Main Idea

Find the volume of

pyramids.

Vocabulary

pyramid

lateral face

V

p

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