Grade 3 Fractions: Adding Fractions

Add fractions with same denominator

What You'll Learn

Add fractions with same denominator
Add numerators, keep denominator
Simplify when possible

📖Adding Fractions

To add fractions with the same denominator, add the numerators and keep the denominator. 2/5 + 1/5 = 3/5. The pieces are the same size, so just count them up!

💡

Only add the top numbers! The bottom number tells you the size of the pieces.

Worked examples

Real problems from the practice worksheets, solved one step at a time.

Example 1
2/6 + 4/6 = ?
1. The denominators are the same (6), so the pieces are the same size.
2. Add the numerators and keep the denominator: 2 + 4 = 6, so the sum is 6/6.
3. 6 sixths make one whole, so 6/6 is 6 ÷ 6 = 1 whole (written 1/1).
4. So 2/6 + 4/6 = 1/1.
Answer: 1
Example 2
7/8 + 4/8 = ?
1. The denominators are the same (8), so the pieces are the same size.
2. Add the numerators and keep the denominator: 7 + 4 = 11, so the sum is 11/8.
3. So 7/8 + 4/8 = 11/8.
Answer: 11/8
Example 3
5/6 + 5/6 = ?
1. The denominators are the same (6), so the pieces are the same size.
2. Add the numerators and keep the denominator: 5 + 5 = 10, so the sum is 10/6.
3. The greatest number that divides both 10 and 6 is 2.
4. Divide the top and bottom by 2: 10 ÷ 2 = 5 and 6 ÷ 2 = 3, so 10/6 = 5/3.
5. So 5/6 + 5/6 = 5/3.
Answer: 5/3