How to Add and Subtract Fractions

Created by Shajan And Jenna

Welcome to our study sheet and your key to success when dealing with fractions!

Here is the section for Adding fractions

Below you will find several videos, explanations, rules and steps on how to add fractions wether it be mixed, improper or even proper fractions.

Mixed Fractions!


  1. Find the (Least Common Denominator)
  2. Find the equivalent fractions.
  3. Add or subtract the fractions and add or subtract the whole numbers.
  4. Write your answer in lowest terms.


There are several rules to adding mixed fractions!

Rule number 1: Always remember to find the LCD (Lowest common denominator) before you start adding! Don't jump right in.

Rule number 2: Always keep the mixed number that you or not using on the side so that you don't forget about it later on.

Rule number 3: As you are adding mixed fractions it is safe for you to keep the mixed numbers aside and then add but, if you are subtracting mixed fractions you would have to change them to an improper fraction.


1 3/4 + 2 5/20=

1 15/20 + 2 5/20=

3 20/20=


Adding mixed numbers
Add Mixed Numbers with Unlike Denominators
Adding Mixed Fractions

Proper fractions!


1.We find the Least Common Denominator (LCD)

2.Rewrite all fractions in our equation to equivalent fractions using the LCD as the denominator.

3.Now that all denominators are the same we add regularly.


Rule number 1: Always remember to find the LCD (Lowest common denominator) before you start adding! Don't jump right in.

Rule number 2: As you add don't add the denominator but only add the two numerators.

Rule number 3: Remember to always lower your final answer and simplify it if possible this means that both numbers are a multiple of each other or have a common multiple which then can be simplified.

Adding Fractions with Unlike Denominators
Adding Simple Fractions
Adding Proper Fractions


1/2 + 2/3=

3/6+ 4/6=


1 1/6

Improper Fractions!


1) First you have to convert the Improper fractions into mixed fractions that is, unless you want to keep it so.If you are keeping it the same you will have to end up converting it into a mixed fraction in the end.

2) From this point if you have converted it to a mixed fraction you follow that method but, if you kept it as an improper fraction you keep going. You have to find the LCD (Lowest Common Denominator.)

3) We do the same that we do the bottom so both the numerator and denominator and multiplied b the amount that it takes to get to your LCD.

4) Now we simply add the numerators and keep the denominator.

5) Finally, we simply the fraction by changing it into a mixed fraction and if possible simplifying it from there.


1) Never forget to change your final fraction into a mixed fraction

2) Don't forget to Simply your final fraction

Quick tip!

If you cant find the LCD just multiply both of them together!

Convert Mixed Numbers into Improper Fractions & Adding Fractions in Two Effective Ways



12/10+ 15/10=


2 7/10