Subtracting Fractions With Unlike Denominators - Varsity Tutors

Home » How To Subtract Fractions With Different Denominators » Subtracting Fractions With Unlike Denominators - Varsity Tutors

Maybe your like

Skip to main contentVarsity Tutors LogoHotMathSubtracting Fractions with Unlike Denominators

Subtracting Fractions with Unlike Denominators

Study Guide

Key Definition

To subtract fractions with unlike denominators, find the least common multiple (LCM) of the denominators and convert each fraction to an equivalent fraction with this common denominator.

Important Notes

  • Find the $LCM$ of the denominators
  • Convert fractions to equivalent fractions with the $LCM$ as the denominator
  • Subtract the numerators
  • Simplify the resulting fraction if possible
  • Check your work by ensuring the fractions are equivalent

Mathematical Notation

$\frac{a}{b}$ means a divided by b$-$ represents subtraction$\times$ or $*$ represents multiplication$\div$ or $/$ represents divisionRemember to use proper notation when solving problems

Why It Works

Finding a common denominator ensures that the fractions are expressed in a way that allows for direct comparison and accurate subtraction.

Remember

The key to subtracting fractions with unlike denominators is finding the $LCM$ and converting each fraction accordingly.

Quick Reference

LCM of 7 and 3:$21$

Understanding Subtracting Fractions with Unlike Denominators

Choose your learning level

Watch & Learn

Video explanation of this concept

concept. Use space or enter to play video.concept thumbnailBeginner

Start here! Easy to understand

BeginnerIntermediateAdvanced

Beginner Explanation

To subtract fractions with different denominators, convert them to have a common denominator using the $LCM$.Now showing Beginner level explanation.

Practice Problems

Test your understanding with practice problems

1

Quick Quiz

Single Choice QuizBeginner

What is $\frac{6}{7} - \frac{2}{3}$?

A$\frac{4}{21}$B$\frac{2}{21}$C$\frac{10}{21}$D$\frac{8}{21}$Check AnswerPlease select an answer for all 1 questions before checking your answers. 1 question remaining.2

Real-World Problem

Question ExerciseIntermediate

Teenager Scenario

If you ate $\frac{3}{4}$ of a pizza and your friend ate $\frac{2}{5}$, how much more pizza did you eat?Show AnswerClick to reveal the detailed solution for this question exercise.3

Thinking Challenge

Thinking ExerciseIntermediate

Think About This

Challenge yourself with $\frac{5}{6} - \frac{3}{8}$. Find the answer.

Show AnswerClick to reveal the detailed explanation for this thinking exercise.4

Challenge Quiz

Single Choice QuizAdvanced

What is $\frac{7}{9} - \frac{5}{12}$?

A$\frac{5}{36}$B$\frac{13}{36}$C$\frac{7}{36}$D$\frac{11}{36}$Check AnswerPlease select an answer for all 1 questions before checking your answers. 1 question remaining.

Recap

Watch & Learn

Review key concepts and takeaways

recap. Use space or enter to play video.recap thumbnail

Tag » How To Subtract Fractions With Different Denominators