Rounding error intervals and bounds
Learn Rounding error intervals and bounds for Years 9–11 pupils (ages 13–16). Free practice questions, lessons and worked examples — aligned to the UK National Curriculum.
What you'll learn
- 1
A rounded measurement stands for a RANGE of possible values, not one exact value.
- 2
A length given as 8 cm to the nearest cm could be anything from 7.5 cm up to (but not including) 8.5 cm.
- 3
A mass is 40 kg to the nearest kg. What is the lower bound?
- 4
The upper bound uses a strict "less than", because 8.5 would itself round up to 9.
- 5
A time is 12.4 s to 1 decimal place. Half of 0.1 is 0.05, so the interval is 12.35 ≤ t < 12.45.
- 6
A length is 25 cm to the nearest 5 cm. What is the interval?
- 7
Why is the upper bound written with < rather than ≤?
Practise Rounding error intervals and bounds with Whizlo
Free AI-tutored lessons, unlimited practice questions, and progress tracking for ages 13–16. Aligned to the UK National Curriculum.