Year 8 - Maths
Checking understanding of rounding
Estimation and rounding
Study Hub
Study Guides
This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
This unit helps pupils understand rounding to different decimal places, and significant figures. Pupils will also learn how to truncate numbers and understand the contexts in which these skills are useful. The unit ends will an exploration of rounding and inequality errors.
Lesson Summary
You will learn to round to the nearest 100 or 10 or whole number or to 1 or 2 decimal places.
Key Notes
- Any number can be rounded to the nearest 10, 100 or 1000.
- A number with one or more decimal places can be rounded to the nearest whole number.
- A number with two or more decimal places can be rounded to one decimal place.
- A number with three or more decimal places can be rounded to two decimal places.
Vocabulary To Learn
- Round: To change a number into another number that is approximately the same value but is easier to work with. E.g. round 561 to the nearest 10 is 560.
Common Mistakes To Avoid
- When rounding a number, pupils write the first significant digit(s) only. E.g 36 789 is 4.
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
Any number can be rounded to the nearest 10, 100 or 1000. A number with one or more decimal places can be rounded to the nearest whole number.
2. Use this key word in a maths sentence and explain it clearly. 'Round'
To change a number into another number that is approximately the same value but is easier to work with. E.g. round 561 to the nearest 10 is 560. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: When rounding a number, pupils write the first significant digit(s) only. E.g 36 789 is 4. Correction: The use of the place value table shows the magnitude of the number, thus preserving their place value.
More Lessons In This Unit
- Checking by estimating Study Guide
- Degrees of accuracy Study Guide
- Estimating numerical calculations Study Guide
- Inequality notation to express error Study Guide
- Overestimating vs underestimating Study Guide
- Problem solving with estimation and rounding Study Guide
- Rounding decimals to significant figures Study Guide
- Rounding errors Study Guide
- Rounding integers to one significant figure Study Guide
- Rounding integers to significant figures Study Guide
- Rounding to any number of decimal places Study Guide
- Rounding to three decimal places Study Guide
- Securing understanding of rounding Study Guide
- Truncating Study Guide
- Using inequality notation for errors in calculations Study Guide
Browse all guides in the Year 8 Maths guide library.