Add and Subtract Fractions with Like Denominators

Working with fractions is as easy as slicing pizza when the denominators match!

Understanding Like Denominators

Fractions with like denominators have the same bottom number!
This means we're working with pieces that are all the same size, making addition and subtraction much easier. Imagine you have two pizzas cut into 8 slices each - you can easily combine or compare slices because they're all the same size!

How to Add and Subtract Fractions with Like Denominators

1️⃣ Keep the denominator the same (the bottom number stays unchanged)

2️⃣ Add or subtract the numerators (the top numbers)

3️⃣ Simplify your answer if possible (reduce to lowest terms)

Let's Practice with Examples!

Example 1: Adding Fractions

Let's add \(\frac{3}{8} + \frac{2}{8}\)

3/8 pizza

+

2/8 pizza

=

?/8 pizza

We keep the denominator (8) and add the numerators: 3 + 2 = 5

\(\frac{3}{8} + \frac{2}{8} = \frac{5}{8}\)

Can we simplify \(\frac{5}{8}\)? No, because 5 and 8 have no common factors other than 1.

Example 2: Subtracting Fractions

Let's subtract \(\frac{7}{10} - \frac{3}{10}\)

7/10 water bottle

-

3/10 water bottle

=

?/10 water bottle

We keep the denominator (10) and subtract the numerators: 7 - 3 = 4

\(\frac{7}{10} - \frac{3}{10} = \frac{4}{10}\)

Can we simplify \(\frac{4}{10}\)? Yes! Both numbers can be divided by 2:

\(\frac{4 ÷ 2}{10 ÷ 2} = \frac{2}{5}\)

Parent Tips 🌟

  • Use real-life examples: Cooking (measuring ingredients), pizza slices, or dividing candy bars make great visual aids for fraction practice.
  • Emphasize the "why": Explain that the denominator is like the "name" of the pieces - we can only combine things that have the same name (like apples with apples).
  • Make it a game: Create fraction cards and have your child race to solve addition/subtraction problems, rewarding speed and accuracy.

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