<marquee>Please copy the notes correctly and think through the steps as they are presented.</marquee>

Now that you can add fractions with like denominators, and you can find equivalent fractions, you are ready to add fractions with unlike denominators.

You will remember that you did not add the denominators previously; you left them as they were. To add fractions with different denominators you must make the denominators the same. You will do this by creating equivalent fractions. You want to make equivalent fractions that have the same denominators as each other, and you want that denominator to be the least common multiple of the two original denominators.

Let’s try this; we’ll add ½ and ¼. These two fractions have different denominators; the least common multiple of 2 and 4 is 4. This means that you must convert ½ into 2/4. Now you can add your fractions, 2/4 and ¼, add the numerators which gives you 3, leave the denominator the same so you have a 4, your fraction is ¾.

Let’s try another example, 2/5 and ½. You cannot add the fractions in this format, they will need to have the same denominator. The least common multiple of 5 and 2 is 10. This time you need to make equivalent fractions for both the fractions in your problem, 2/5, multiplied by 2 over 2, becomes 4/10 and ½ multiplied by 5 over 5 becomes 5/10. You now have two fractions you can add, 4/10 and 5/10 so go ahead and add your fractions. Add the numerators and you have 9, the denominator stays the same so you have 10, your fraction is 9/10.

Please move on to the practice page and take the quiz when you are ready.