Adding and subtracting fractions with the same bottom number

Mathematics · Fractions · ages 8-9

Name ______________________ Date ____________

Add 5/9 + 6/9. How many ninths are in the total? Type the numerator.
Answer: ______________
What is 2/7 + 3/7?
- 5/7
- 5/14
- 6/7
- 1/7
What is 7/9 - 6/9?
- 1/9
- 1/18
- 13/9
- 2/9
1/3 + 2/3 equals one whole.
Circle one: True False
What is 7/8 + 3/8?
- 10/8
- 10/16
- 11/8
3/5 + 4/5 = ?/5. What number goes on top?
Answer: ______________
Which fraction can you take from 8/11 to leave 5/11?
- 2/11
- 4/11
- 5/11
- 3/11
What is 5/6 + 5/6?
- 10/12
- 5/6
- 25/6
- 10/6
What is 11/6 written as a mixed number?
- 1 4/6
- 1 5/6
- 2 5/6
Leo calculated 5/8 + 6/8 and wrote the answer as 11/16. What mistake did Leo make?
- He subtracted the top numbers instead of adding them.
- He multiplied the top numbers instead of adding them.
- He added the bottom numbers instead of keeping them.

Answer key

For grown-ups. Fold this page away before handing over the rest.

11 · 5 + 6 = 11, so the total is eleven ninths.
5/7 · 2 + 3 = 5. Keep sevenths, giving 5/7.
1/9 · 7 - 6 = 1. One ninth remains.
True · 1 + 2 = 3. Three thirds fill one whole.
10/8 · Add the top numbers: 7 + 3 = 10. The bottom number stays 8, so the answer is 10/8.
7 · Add the top numbers: 3 + 4 = 7. So 3/5 + 4/5 = 7/5.
3/11 · Eight pieces minus five remaining pieces means three were removed.
10/6 · Ten sixth-pieces give 10/6.
1 5/6 · Six sixths make one whole. Five sixths remain, giving 1 5/6.
He added the bottom numbers instead of keeping them. · The bottom number should stay 8. The correct answer is 11/8, which is 1 3/8.