DfE statement N16 · Number

Limits of accuracy and bounds

part HigherCalculator

Limits of accuracy and bounds is content statement N16 of the DfE GCSE mathematics subject content, in the number area. It is on both tiers, with a Higher-only part, and it is normally a calculator-paper question. Below is what the specification actually requires, the 3 mistakes that cost marks on this topic most often, and practice questions written to the statement — original questions, not past papers.

What the specification says

The DfE subject content for GCSE mathematics states, verbatim: "Apply and interpret limits of accuracy, including upper and lower bounds." (statement N16). Every awarding organisation — Pearson Edexcel, AQA and OCR — must cover it, so the wording is the same whichever specification your school follows.
— Department for Education, Mathematics: GCSE subject content and assessment objectives, statement N16

Tier

Both tiers, but part of it is Higher only. Foundation covers the statement except for the following, which the DfE prints in bold and reserves for Higher: "upper and lower bounds". Everything else in the statement is Foundation content.

Calculator

This is calculator work, which places it on Papers 2 and 3. Know your own calculator before the exam, keep full accuracy through the working and round only at the end.

Common mistakes

Halving the wrong unit: a length given to the nearest centimetre has bounds ±0.5 cm, not ±0.05 cm.
Using the upper bound of both quantities in a subtraction. For the largest possible difference, take the upper bound of the first minus the lower bound of the second.
Dividing upper bound by upper bound. The largest quotient comes from the largest numerator over the smallest denominator.

Sample questions (10 of 30)

N16 · Limits of accuracy and boundsQuestion 1 of 10 · 0 correct

Practice mode· no pressure · hints available

Number

N16

Intermediate

The rainfall in a town during April is recorded as 62.4 mm, correct to 1 decimal place. Write down the error interval for the actual rainfall, r mm.

💡 Hints:

Foundation worksheet Higher worksheet Foundation number practice Higher number practice

Nearby statements

N1Ordering numbers and inequality symbols N2The four operations and place value N3Inverse operations and priority of operations

Questions people ask

Is limits of accuracy and bounds on Foundation or Higher?

Both, but not all of it. The parts the DfE prints in bold — "upper and lower bounds" — are Higher only; the rest is Foundation content.

Can I use a calculator for limits of accuracy and bounds?

Yes, on Papers 2 and 3, which are the calculator papers and where questions on this usually sit. Paper 1 is non-calculator.

What is the single most common mistake here?

Halving the wrong unit: a length given to the nearest centimetre has bounds ±0.5 cm, not ±0.05 cm.

Are these past paper questions?

No. Every question is original, written to this DfE content statement and checked before publication. We do not host past papers or mark schemes.

Back to Number at Foundation or at Higher.