Fractions whose denominators are the same are called **similar fractions**, otherwise they are called **dissimilar fractions**. The fractions 1/9 and 7/9 are similar fractions, while 3/4 and 2/3.

Adding similar fractions is easy. Just copy add the **numerator** and then copy the **denominator**. For example,

**1**/9 +** 7**/9 = 8/9.

Adding dissimilar fractions is a bit more complicated. You have to get the Least Common Multiple (LCM) of the denominators. For example, if we want to add 3/4 and 2/3, we get the LCM of 4 and 3 which is equal to 12. You then change the given to equivalent fractions. The addition becomes

9/12 + 8/12 = 17/12.

**Shortcut: How to Add Two Fractions Faster**

We can use a shortcut to add to two add fractions. We will only discuss dissimilar fractions because similar fractions are too easy to add. Below are the steps for the shortcut **3**/**4 and 2**/**3**.

**Example 1: 3/4 + 2/3**

(1) Multiply the numerator of the first fraction by the denominator of the second fraction: **3** ×** 3** = 9.

(2) Multiply the denominator of the first fraction by the numerator of the second fraction: 4 × 2 = 8

(3) Add the results in (1) and (2). The sum is the numerator of the sum: 9 + 9 = 17.

(4) Multiply the denominators of the given. This will be the numerator of the sum: **4** × **3** = 12.

So, the answer to the addition is 17/12.

**Example 2: 2/7 + 5/9**

**Example 3: 4/5 + 7/9**

In the next post, we are going to discuss why this shortcut works.

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