Lesson: Subtracting fractions with Same Denominators

Introduction

In this lesson, we will learn how to subtract fractions that have the same denominator. When fractions share a common denominator, we can easily subtract the numerators while keeping the denominator the same.

Key Concept

When subtracting fractions with the same denominator, use the formula:

$$\frac{a}{c} - \frac{b}{c} = \frac{a - b}{c}$$

Where:

• $a$ and $b$ are the numerators,
• $c$ is the common denominator.

Steps to Subtract fractions

1. Identify the denominators: Ensure that the denominators are the same.
2. Subtract the numerators: Perform the subtraction on the numerators.
3. Keep the denominator: Write the result over the common denominator.

Example

Let's subtract the fractions $\frac{5}{8}$ and $\frac{3}{8}$.

1. Identify the denominators: Both fractions have a denominator of 8.
2. Subtract the numerators: $5 - 3 = 2$.
3. Keep the denominator: The result will be $\frac{2}{8}$.

Now, we can simplify $\frac{2}{8}$ to $\frac{1}{4}$.

So, $\frac{5}{8} - \frac{3}{8} = \frac{1}{4}$.

Key Questions

• What do you do with the denominators when subtracting fractions with the same denominator?
• How do you simplify the result after subtracting?
• Can you provide another example of subtracting fractions with the same denominator?

Summary

Subtracting fractions with the same denominator is straightforward: subtract the numerators and keep the denominator the same. Remember to simplify your answer if possible.