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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

CCSS.Math:
5.MD.C.5
,
5.MD.C.5c
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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