Handout
Other

Help With Fractions: Least Common Denominator

For Students 3rd - 8th Standards
The rules for finding the least common denominator are clearly explained at this website. Two different methods are given. This is an excellent place to get step by step explanations for working with fractions.
Handout
Quia

Ixl Learning: Least Common Denominator

For Students 3rd - 5th Standards
Brush up on your math skills relating to the least common denominator then try some practice problems to test your understanding.
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Finding the Least Common Denominator

For Students 4th - 5th
[Free Registration/Login may be required to access all resource tools.] In this learning module, students must find the least common denominator for the fractions they are presented with. Includes video demonstrating a sample problem...
Handout
Varsity Tutors

Varsity Tutors: Hotmath: Algebra Review: Least Common Denominator

For Students 9th - 10th Standards
Find a quick, concise explanation of how to find the least common denominator for fractions or rational expressions. Examples are given and clearly explained.
Interactive
Calculator Soup

Calculator Soup: Lcd Calculator Least Common Denominator

For Students 9th - 10th
Use this Least Common Denominator Calculator to find the lowest common denominator (LCD) of fractions, integers and mixed numbers. Finding the LCD is important because fractions need to have the same denominator when you are doing...
Handout
Quia

Ixl Learning: Least Common Multiple

For Students 5th - 6th Standards
Brush up on your math skills relating to the least common multiple then try some practice problems to test your understanding.
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Comparing Fractions Using Lcm Word Problems

For Students 4th - 5th Standards
[Free Registration/Login may be required to access all resource tools.] For this learning module, students are asked to compare fractions in word problems and determine which is bigger or smaller. Includes video demonstrating a sample...
PPT
Sophia Learning

Sophia: Comparing Fractions With Unlike Denominators

For Students 6th - 8th
Students watch a video lesson about comparing fractions with unlike denominators. The tutorial includes an example using common denominators.
PPT
Sophia Learning

Sophia: Comparing Fractions With Unlike Denominators

For Students 6th - 8th
Students review how to compare fractions with unlike denominators. The video tutorial includes detailed examples.
Whiteboard
Other

Active Maths Limited: Adding & Subtracting Fractions: Whiteboard Resources

For Students 3rd - 8th Standards
This is an excellent resource to visually illustrate adding and subtracting fractions by finding the lowest common denominator.
Unit Plan
Math Is Fun

Math Is Fun: Least Common Denominator

For Students 3rd - 8th
The learning activity examines the least common denominator. Topics include fractions with denominators, common denominators, and the least common denominator. The resource consists of images, explanations, examples with solutions, and a...
Unit Plan
CK-12 Foundation

Ck 12: Fraction Comparison With Lowest Common Denominators

For Students 6th
[Free Registration/Login may be required to access all resource tools.] Compare fractions using lowest common denominators.
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Subtracting Fractions With Different Denominators

For Students 4th - 5th Standards
[Free Registration/Login may be required to access all resource tools.] In this learning module, students must find the least common denominator of two fractions in order to subtract one from the other. Includes video demonstrating a...
Unit Plan
Khan Academy

Khan Academy: Common Denominators

For Students 3rd - 5th
Practice rewriting fractions to have the same denominator. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Unknown Type
Khan Academy

Khan Academy: Common Denominators

For Students 3rd - 5th Standards
In this exercise, students practice finding common denominators. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
eBook
CK-12 Foundation

Ck 12: 2.3 Adding and Subtracting Rational Expressions

For Students 9th - 10th Standards
This section explores the process for adding and subtracting rational expressions. It primarily focuses on how to identify and use the Least Common Denominator to combine fractions with rational expressions.
Handout
Homeschool Math

Homeschool Math: Finding the (Least) Common Denominator

For Teachers 5th
Students learn about finding a common denominator in fraction addition and subtraction.
Unit Plan
CK-12 Foundation

Ck 12: Elem Math: Ordering Fractions With Different Denominators

For Students 4th - 5th
[Free Registration/Login may be required to access all resource tools.] For this learning module, students are asked to compare fractions with different denominators and put them in order. Includes video demonstrating a sample problem...
Handout
Cool Math

Coolmath: Coolmath4kids: Adding and Subtracting Fractions With Different Denominators

For Students 4th - 5th Standards
Demonstrates how to add and subtract fractions where the denominators are different. Includes sample problems to try.
Unit Plan
CK-12 Foundation

Ck 12: Arithmetic: Fraction Ordering With Lowest Common Denominators

For Students 6th
[Free Registration/Login may be required to access all resource tools.] Order fractions from least to greatest and greatest to least using lowest common denominators.
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: Finding Common Denominators to Add

For Teachers 5th - 8th Standards
Part (a) of this task asks students to find and use two different common denominators to add the given fractions. The purpose of this question is to help students realize that they can use any common denominator to find a solution, not...
Lesson Plan
Illustrative Mathematics

Illustrative Mathematics: Finding Common Denominators to Subtract

For Teachers 5th - 8th Standards
Part (a) of this task asks students to use two different denominators to subtract fractions. The purpose of this is to help students realize that any common denominator will work, not just the least common denominator. Part (b) does not...
Handout
Math Is Fun

Math Is Fun: Definition of Common Denominator

For Students 3rd - 8th Standards
Definitiion of a common denominator with examples.
Unit Plan
Houghton Mifflin Harcourt

Houghton Mifflin Harcourt: Saxon Activity Center: Graphing Calculator Activity: Common Denominators [Pdf]

For Students 9th - 10th Standards
A graphing calculator lesson focusing on common denominator. Lesson contains detailed examples, visual demonstrations with key functions, and practice problems. Acrobat Reader required.