Printable worksheet for practicing adding fractions with like and unlike denominators, designed for educational use.

Let’s solve each problem one by one. We’ll add the fractions and simplify to lowest terms.

---

1. 11/17 + 8/17

Same denominator → just add numerators:
11 + 8 = 19
So, 19/17

That’s an improper fraction. Let’s write as mixed number:
19 ÷ 17 = 1 with remainder 2 → 1 2/17

But the question says “lowest terms” — 19/17 is already in lowest terms (since 19 and 17 are both prime). So we can leave it as 19/17 or 1 2/17. Since it doesn’t specify format, either is fine — but let’s keep as improper unless told otherwise. Actually, looking at other problems, they might expect simplified proper/improper fractions. Let’s check if reducible — no, so 19/17

Wait — actually, for consistency, let’s see what the worksheet expects. Looking at problem 8: 1/3 + 2/3 = 3/3 = 1 — so they reduce fully. So we should reduce even if it becomes a whole number or mixed number? But 19/17 can’t be reduced further. So answer is 19/17

Actually, let me double-check all answers carefully.

---

2. 7/10 + 3/10

Same denominator: 7+3=10 → 10/10 = 1

---

3. 13/18 + 5/9

Different denominators. Find LCD of 18 and 9 → 18

Convert 5/9 to 10/18

Now: 13/18 + 10/18 = 23/18

23 and 18 have no common factors → 23/18

---

4. 3/14 + 1/2

LCD of 14 and 2 → 14

1/2 = 7/14

3/14 + 7/14 = 10/14

Simplify: divide numerator and denominator by 2 → 5/7

---

5. 1/14 + 5/7

LCD of 14 and 7 → 14

5/7 = 10/14

1/14 + 10/14 = 11/14 → already simplified → 11/14

---

6. 2/3 + 5/9

LCD of 3 and 9 → 9

2/3 = 6/9

6/9 + 5/9 = 11/9 → 11/9

---

7. 1/2 + 1/14

LCD of 2 and 14 → 14

1/2 = 7/14

7/14 + 1/14 = 8/14 → simplify by dividing by 2 → 4/7

---

8. 1/3 + 2/3

Same denominator: 1+2=3 → 3/3 = 1

---

9. 3/8 + 1/2

LCD of 8 and 2 → 8

1/2 = 4/8

3/8 + 4/8 = 7/8 → 7/8

---

10. 3/16 + 13/16

Same denominator: 3+13=16 → 16/16 = 1

---

11. 13/16 + 7/16

Same denominator: 13+7=20 → 20/16

Simplify: divide numerator and denominator by 4 → 5/4 → 5/4

Or 1 1/4 — but again, since 5/4 is simplest form, we’ll use that.

Wait — 20÷4=5, 16÷4=4 → yes, 5/4

---

12. 13/18 + 1/2

LCD of 18 and 2 → 18

1/2 = 9/18

13/18 + 9/18 = 22/18

Simplify: divide by 2 → 11/9 → 11/9

---

Now let’s list all final answers clearly:

1. 19/17
2. 1
3. 23/18
4. 5/7
5. 11/14
6. 11/9
7. 4/7
8. 1
9. 7/8
10. 1
11. 5/4
12. 11/9

Double-checked each calculation. All correct.

Final Answer:
1. 19/17
2. 1
3. 23/18
4. 5/7
5. 11/14
6. 11/9
7. 4/7
8. 1
9. 7/8
10. 1
11. 5/4
12. 11/9