Add & Subtract Fractions with Unlike Denominators

Learn how to combine and compare fractions with different bottom numbers!

Understanding Unlike Denominators

Fractions can be tricky when their denominators (the bottom numbers) are different!
But don't worry - we have a super strategy to solve these problems. The key is to find a common denominator before adding or subtracting. Think of it like speaking the same "fraction language" before combining them!

The 3-Step Strategy

1️⃣ Find a common denominator (the smallest number both denominators divide into)

2️⃣ Convert both fractions to equivalent fractions with this denominator

3️⃣ Add or subtract the numerators (top numbers) and keep the denominator

Let's Practice Together!

Example 1: Adding Fractions

Let's solve: \(\frac{1}{2} + \frac{1}{4} = ?\)

1 part out of 2
+
1 part out of 4

Step 1: The denominators are 2 and 4. The smallest common denominator is 4.

Step 2: Convert \(\frac{1}{2}\) to fourths: \(\frac{1}{2} = \frac{2}{4}\)

Step 3: Now add: \(\frac{2}{4} + \frac{1}{4} = \frac{3}{4}\)

🍕 Pizza analogy: If you have half a pizza (2/4) and add another quarter (1/4), you get three quarters (3/4)!

Example 2: Subtracting Fractions

Let's solve: \(\frac{5}{6} - \frac{1}{3} = ?\)

5 parts out of 6
-
1 part out of 3

Step 1: The denominators are 6 and 3. The smallest common denominator is 6.

Step 2: Convert \(\frac{1}{3}\) to sixths: \(\frac{1}{3} = \frac{2}{6}\)

Step 3: Now subtract: \(\frac{5}{6} - \frac{2}{6} = \frac{3}{6}\) which simplifies to \(\frac{1}{2}\)

🍫 Candy bar analogy: If you have 5/6 of a candy bar and give away 1/3 (which is 2/6), you're left with 3/6 or half!

Parent Tips 🌟

  • Kitchen Math: Use measuring cups to demonstrate fractions in cooking - show how 1/2 cup plus 1/4 cup makes 3/4 cup.
  • Visual Aids: Draw fraction circles or bars to help visualize the concept of common denominators.
  • Real-world Problems: Create word problems using allowance money or time management to practice these skills in context.

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