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5th grade

Course: 5th grade > Unit 11

Lesson 3: Decompose figures to find volume
Math
5th grade
Volume
Decompose figures to find volume
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Decompose figures to find volume practice

Google Classroom
Work through volume of irregular 3D figures problems that get increasingly more challenging.  The first items will have unit cubes.  Then, try some with only side-length labeled.

Decompose figures with unit cubes

Problem 1A
Unit cube:
A unit cube is shown.
What is the volume of the following figure?
Front ViewBack View
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
unit cubes

Problem 1B
Unit cube:
A unit cube is shown.
What is the volume of the following figure?
Front ViewBack View
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
unit cubes

Want to practice more problems like this? Check out this exercise.

Decompose figures with side-length labels

Problem 2B
The figure below is made of 2 rectangular prisms.
What is the volume of this figure?
A shape made up of two rectangular prisms. The first rectangular prism has a base that measures 2 inches length by 6 inches width, and has a height of 5 inches. The second rectangular prism sits behind the first rectangular prism. It has a base that measures 8 inches length by 1 inch width and has a height of 5 inches.
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
start text, c, u, b, i, c, space, i, n, end text

Problem 2A
The figure below is made of 2 rectangular prisms.
What is the volume of this figure?
A figure made up of 2 rectangular prisms. The first rectangular prism has the dimensions 10 centimeters length by 6 centimeters width by 3 centimeters height. The second rectangular prism has the dimensions 4 centimeters length by 6 centimeters width by 4 centimeters height.
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
start text, c, u, b, i, c, space, c, m, end text

Want to practice more problems like this? Check out this exercise.

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