Digits, Grade 7, Volume 1, Homework Helper

5-5: Volumes of Right Pyramids

Key Concept

The volume of a pyramid is the number of unit cubes needed to fill the pyramid.

The formula for the volume of a pyramid is 1 third the product of the base area and the height of the pyramid

Suppose you have a pyramid and a prism with the same base and the same height. By turning these solid figures into containers, you can show a relationship between their volumes. Find out how many containers of the pyramid it takes to fill the prism.

It takes three containers of the pyramid to fill the prism. So the volume of the prism is three times the volume of the pyramid. This means that the volume of the pyramid is 1 third the volume of the prism.

Remember that the volume of a prism is equal to the area of the base times the height.

table with 3 rows and 2 columns , row1 column 1 , volumeofpyramid , column 2 equals , 1 third , . openvolumeofprismclose , row2 column 1 , volumeofpyramid , column 2 equals , 1 third , . openareaofbase . middle dot , heightclose , row3 column 1 , v , column 2 equals , 1 third b h , end table


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Table of Contents

Digits, Grade 7, Volume 1, Homework Helper Unit A: Number and Operations Unit B: Expressions, Equations, and Relationships Unit C: Measurement and Geometry Unit D: Proportionality English/Spanish Glossary Formulas Math Symbols Formulas Measures Properties