Subtracting Fractions with Different Denominators

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Objective

I can subtract fractions with unlike denominators by finding a common denominator.

Part 1 of 4

Warm-up video

Math with Mr. J · 8:38Vetted channel

We don't generate video — this one is by Math with Mr. J on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.

Part 2 of 4

Key concepts

3 concepts

  1. 1

    When subtracting fractions with unlike denominators, you must first find a common denominator by finding the least common multiple between the denominators.

  2. 2

    To rename a fraction, multiply both the numerator and the denominator by the same number to get an equivalent fraction with the common denominator.

  3. 3

    After subtracting the numerators, always check to see if the answer can be simplified by dividing the numerator and denominator by their greatest common factor.

Part 3 of 4

Practice

12 questions

1

What is the first step in subtracting fractions with unlike denominators?

2

Why is it beneficial to find the least common multiple (LCM) when subtracting fractions?

Part 4 of 4

Exit ticket

Quick comprehension check

Solve: ⅚ - ⅜. Show all steps, including finding a common denominator and simplifying your answer.

Sample answer included in the free materials

Get the materials

Teacher guide, student handout, and slides — free, in Google Docs format

  • Teacher Guide

    Complete lesson plan with answer keys and alternate activities

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