Grade 5 · Maths · Lessons
Fraction stories
🥣cup🧃juice🎀ribbon🔍estimate
Fraction stories.The big ideaSay about how much first. Then cut to one bottom, or multiply across, and check the size.
How it works
Say about how much first. Then cut to one bottom, or multiply across, and check the size.
To add fractions with different bottoms, cut them to the same bottom.
An estimate tells you if your answer is sensible.
Example 1: Add
- Mia pours 1/8 of a cup of flour and then 3/4 of a cup.
- 3/4 is 6/8, so 1/8 + 6/8 = 7/8.
- She has 7/8 of a cup, a bit less than a cup.
Example 2: Take away
- Leo has 5/6 of a liter and drinks 1/12 of a liter.
- 5/6 is 10/12, so 10/12 − 1/12 = 9/12.
- 9/12 is 3/4 of a liter.
Example 3: Estimate
- Ava cuts 1/12 of a meter and 1/4 of a meter.
- 1/12 is small and 1/4 is a quarter.
- About 1/2 of a meter at most: it's about a third.
Words to know
- common bottom
- A bottom number both fractions can share.
- estimate
- A close answer.
Watch out
- Cut to the same bottom before adding.
- Estimate first.
- Simplify at the end.
Try it
- 1/2 + 1/4 = ?
- 2/3 − 1/6 = ?
- Is 1/3 + 1/4 more or less than 1/2?
- What do you do before adding fractions with different bottoms?
Answers: 1. 3/4 · 2. 1/2 · 3. more · 4. cut them to the same bottom
For grown-upsCook with fractions of a cup and talk through the adding.