Add and subtract fractions with like denominators
When fractions have the same denominator (bottom number), adding and subtracting is easy! You're just combining or removing pieces of the same size.
Concept
Adding and subtracting fractions with like denominators is straightforward! šÆ **The Rule:** When denominators are the same, add or subtract the NUMERATORS only. The denominator stays the same! **Addition Example:** 2/5 + 1/5 = ? Think about it: 2 fifths + 1 fifth = 3 fifths 2/5 + 1/5 = (2+1)/5 = 3/5 Visual: [Show 2 shaded pieces + 1 shaded piece = 3 shaded pieces, all out of 5] **Subtraction Example:** 4/6 - 1/6 = ? Think: 4 sixths - 1 sixth = 3 sixths 4/6 - 1/6 = (4-1)/6 = 3/6 = 1/2 (simplified) š” **Step-by-Step Process:** **Example: 3/8 + 2/8** Step 1: Check that denominators are the same ā (both 8) Step 2: Add the numerators: 3 + 2 = 5 Step 3: Keep the denominator: 8 Step 4: Write answer: 5/8 Step 5: Simplify if possible (5/8 is already simplified) **Example: 5/7 - 2/7** Step 1: Check denominators ā (both 7) Step 2: Subtract numerators: 5 - 2 = 3 Step 3: Keep denominator: 7 Step 4: Answer: 3/7 š **Important Reminders:** ā¢ Only add/subtract the TOP numbers (numerators) ā¢ The BOTTOM number (denominator) stays the same ā¢ Simplify your answer when possible ā¢ Your answer should be less than or equal to 1 whole (unless you have mixed numbers) šØ **Pizza Model:** 3/8 + 2/8 = ? Imagine a pizza cut into 8 slices: ā¢ You have 3 slices (3/8) ā¢ Your friend gives you 2 more slices (2/8) ā¢ Now you have 5 slices out of 8 (5/8) š **Common Scenarios:** **Getting a whole:** 4/5 + 1/5 = 5/5 = 1 (All 5 pieces make 1 whole!) **Subtracting to get zero:** 3/4 - 3/4 = 0/4 = 0
Try it
Practice adding and subtracting fractions! š **Add These Fractions:** 1. 1/6 + 2/6 = ? 2. 3/8 + 4/8 = ? 3. 2/5 + 2/5 = ? 4. 1/10 + 3/10 = ? š¢ **Subtract These Fractions:** 5. 5/7 - 2/7 = ? 6. 4/9 - 1/9 = ? 7. 6/8 - 2/8 = ? 8. 7/10 - 3/10 = ? šÆ **Mixed Operations:** 9. 2/6 + 3/6 = ? (simplify your answer) 10. 8/12 - 3/12 = ? (simplify your answer) š **Word Problems:** 11. Sarah ran 3/10 of a mile in the morning and 4/10 of a mile in the afternoon. How far did she run total? 12. Marcus had 7/8 of a pizza. He ate 3/8 of it. How much pizza is left? 13. A recipe needs 2/4 cup of sugar for cookies and 1/4 cup for frosting. How much sugar total? šŖ **Challenge:** 14. What fraction do you add to 2/5 to get 4/5? 15. If 5/6 - ? = 1/6, what goes in the box? 16. 1/8 + 2/8 + 3/8 = ? šØ **Create Your Own:** 17. Draw a picture showing 3/10 + 4/10 = 7/10