Adding Fractions with Like Denominators

Adding Fractions with Like Denominators 🍕

Every fraction has two parts:

• The numerator is the top number. It tells you how many pieces you have.
• The denominator is the bottom number. It tells you what size the pieces are.

Like denominators just means the bottom numbers are the same. When the bottoms match, the pieces are all the same size — so they are easy to add!

Examples of like denominators:

• $\frac{1}{4}$ and $\frac{3}{4}$ — both have a 4 on the bottom
• $\frac{2}{5}$ and $\frac{4}{5}$ — both have a 5 on the bottom
• $\frac{3}{8}$ and $\frac{5}{8}$ — both have an 8 on the bottom

Think of it like counting the same kind of pieces. If everything is cut into eighths, you can just count the eighths!

The Simple Rule ✏️

When the denominators are the same, follow these steps:

1. Add the numerators (the top numbers).
2. Keep the denominator the same (do not add the bottoms!).
3. Simplify the answer if you can.

Here it is as a picture:

$\frac{1}{8} + \frac{3}{8} = \frac{1 + 3}{8} = \frac{4}{8}$

Visual Model: Pizza Slices 🍕

Problem: $\frac{1}{8} + \frac{3}{8}$

Imagine a pizza cut into :

Quick Check ✅

Let's make sure the main idea is clear.

Step-by-Step Examples 📝

Let's work through a few problems carefully, one step at a time.

Example 1: $\frac{2}{5} + \frac{1}{5}$

Guided Practice — Choose the Answer 🎯

Add the fractions. Remember: add the tops, keep the bottom.

Build the Answer 🧩

For the problem $\frac{2}{9} + \frac{5}{9}$, choose the correct numerator and the correct denominator for the answer.

Fractions in the Real World 🌎

Adding fractions with like denominators shows up all the time in everyday life.

🥣 Measuring Cups

A recipe needs $\frac{1}{3}$ cup of oil, and then $\frac{2}{3}$ cup more.

Review: What You Learned 🌟

You can now add fractions that have the same denominator. Here's the whole idea in one table:

Situation	What to do	Example
Same denominators	Add tops, keep bottom	$\frac{2}{5} + \frac{1}{5} = \frac{3}{5}$