# WST03 Estimation, confidence intervals and tests Topic Questions

> Edexcel IAL WST03: every Estimation, confidence intervals… topic question from 21 papers (2014–2026), grouped by syllabus point. 181 questions, 587 marks,…

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Edexcel IAL · Mathematics · WST03 · A Level

Every WST03 Estimation, confidence intervals and tests topic question from the 2014–current syllabus, drawn from 21 papers (2014–2026) and grouped by syllabus point. Each row opens a page listing the exact question numbers, marks and a direct link into the paper. These are questions by topic, not full papers, so you can revise one topic at a time.

- WST03
- 8 subtopics
- 181 topic questions
- 21 papers
- 587 tagged marks
- [Back to Estimation, confidence intervals and tests](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/)
- [All paper codes](https://www.examsci.com/topics/)

Core finding

**3.1 Concepts of standard error, estimator, bias. is the most frequently assessed subtopic in Estimation, confidence intervals and tests, with 58 topic questions and 149 marks across 19 papers.** 3.6 Use of Central Limit theorem to extend hypothesis tests… follows with 38 topic questions and 96 marks. The topic contains 8 subtopics, 181 topic questions and 587 marks in total. Rows count only the parts tagged to that subtopic, keep the same colour in both charts and repeat paper count, tagged marks and year range in the native table.

## Topic question count and mark distribution

Subtopics are on the vertical axis and sorted from highest to lowest. Only the parts whose knowledge graph matches a subtopic are counted for it, and percentages are each row's share of the tagged total in that chart. A part tagged to several subtopics is counted in each bar, so the bars are not a partition of the topic total.

### Questions by subtopic

question items

- [3.1 Concepts of standard error, estimator, bias.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-1-concepts-of-standard-error-estimator-bias/) (19 papers) — 58 · 25.0%
- [3.6 Use of Central Limit theorem to extend hypothesis tests and confidence intervals to samples from non-Normal distributions. Use of large sample results to extend to the case in which the variance is unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-6-use-of-central-limit-theorem-to-extend-hypothesis-tests-and-confidence-intervals/) (19 papers) — 38 · 16.4%
- [3.8 Use of large sample results to extend to the case in which the population variances are unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-8-use-of-large-sample-results-to-extend-to-the-case-in-which-the-population/) (19 papers) — 34 · 14.7%
- [3.4 Confidence limits for a Normal mean, with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-4-confidence-limits-for-a-normal-mean-with-variance-known/) (18 papers) — 30 · 12.9%
- [3.2 The distribution of the sample mean $\overline{X}$.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-2-the-distribution-of-the-sample-mean-overline-x/) (14 papers) — 24 · 10.3%
- [3.3 Concept of a confidence interval and its interpretation.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-3-concept-of-a-confidence-interval-and-its-interpretation/) (16 papers) — 23 · 9.9%
- [3.7 Hypothesis test for the difference between the means of two Normal distributions with variances known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-7-hypothesis-test-for-the-difference-between-the-means-of-two-normal-distributions/) (14 papers) — 18 · 7.8%
- [3.5 Hypothesis tests for the mean of a Normal distribution with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-5-hypothesis-tests-for-the-mean-of-a-normal-distribution-with-variance-known/) (7 papers) — 7 · 3.0%

### Marks by subtopic

marks

- [3.8 Use of large sample results to extend to the case in which the population variances are unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-8-use-of-large-sample-results-to-extend-to-the-case-in-which-the-population/) (19 papers) — 157 · 19.2%
- [3.1 Concepts of standard error, estimator, bias.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-1-concepts-of-standard-error-estimator-bias/) (19 papers) — 149 · 18.2%
- [3.4 Confidence limits for a Normal mean, with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-4-confidence-limits-for-a-normal-mean-with-variance-known/) (18 papers) — 123 · 15.0%
- [3.7 Hypothesis test for the difference between the means of two Normal distributions with variances known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-7-hypothesis-test-for-the-difference-between-the-means-of-two-normal-distributions/) (14 papers) — 103 · 12.6%
- [3.6 Use of Central Limit theorem to extend hypothesis tests and confidence intervals to samples from non-Normal distributions. Use of large sample results to extend to the case in which the variance is unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-6-use-of-central-limit-theorem-to-extend-hypothesis-tests-and-confidence-intervals/) (19 papers) — 96 · 11.7%
- [3.2 The distribution of the sample mean $\overline{X}$.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-2-the-distribution-of-the-sample-mean-overline-x/) (14 papers) — 88 · 10.8%
- [3.3 Concept of a confidence interval and its interpretation.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-3-concept-of-a-confidence-interval-and-its-interpretation/) (16 papers) — 75 · 9.2%
- [3.5 Hypothesis tests for the mean of a Normal distribution with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-5-hypothesis-tests-for-the-mean-of-a-normal-distribution-with-variance-known/) (7 papers) — 27 · 3.3%

## Subtopic comparison matrix

Curriculum order is by syllabus number, then alphabetically. Every row links to the matching past-paper question list.

| Subtopic | Topic questions | Papers | Marks | Years | |
| --- | --- | --- | --- | --- | --- |
| **[3.1 Concepts of standard error, estimator, bias.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-1-concepts-of-standard-error-estimator-bias/)** | 58 | 19 | 149 | 2014–2026 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-1-concepts-of-standard-error-estimator-bias/) |
| **[3.2 The distribution of the sample mean $\overline{X}$.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-2-the-distribution-of-the-sample-mean-overline-x/)** | 24 | 14 | 88 | 2014–2026 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-2-the-distribution-of-the-sample-mean-overline-x/) |
| **[3.3 Concept of a confidence interval and its interpretation.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-3-concept-of-a-confidence-interval-and-its-interpretation/)** | 23 | 16 | 75 | 2015–2026 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-3-concept-of-a-confidence-interval-and-its-interpretation/) |
| **[3.4 Confidence limits for a Normal mean, with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-4-confidence-limits-for-a-normal-mean-with-variance-known/)** | 30 | 18 | 123 | 2015–2026 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-4-confidence-limits-for-a-normal-mean-with-variance-known/) |
| **[3.5 Hypothesis tests for the mean of a Normal distribution with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-5-hypothesis-tests-for-the-mean-of-a-normal-distribution-with-variance-known/)** | 7 | 7 | 27 | 2016–2024 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-5-hypothesis-tests-for-the-mean-of-a-normal-distribution-with-variance-known/) |
| **[3.6 Use of Central Limit theorem to extend hypothesis tests and confidence intervals to samples from non-Normal distributions. Use of large sample results to extend to the case in which the variance is unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-6-use-of-central-limit-theorem-to-extend-hypothesis-tests-and-confidence-intervals/)** | 38 | 19 | 96 | 2015–2026 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-6-use-of-central-limit-theorem-to-extend-hypothesis-tests-and-confidence-intervals/) |
| **[3.7 Hypothesis test for the difference between the means of two Normal distributions with variances known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-7-hypothesis-test-for-the-difference-between-the-means-of-two-normal-distributions/)** | 18 | 14 | 103 | 2016–2026 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-7-hypothesis-test-for-the-difference-between-the-means-of-two-normal-distributions/) |
| **[3.8 Use of large sample results to extend to the case in which the population variances are unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-8-use-of-large-sample-results-to-extend-to-the-case-in-which-the-population/)** | 34 | 19 | 157 | 2014–2026 | [Open topic questions](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-8-use-of-large-sample-results-to-extend-to-the-case-in-which-the-population/) |

## Browse every topic question

- [3.1 Concepts of standard error, estimator, bias.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-1-concepts-of-standard-error-estimator-bias/) — 58 question items · 19 papers — 149 marks · 2014–2026
- [3.2 The distribution of the sample mean $\overline{X}$.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-2-the-distribution-of-the-sample-mean-overline-x/) — 24 question items · 14 papers — 88 marks · 2014–2026
- [3.3 Concept of a confidence interval and its interpretation.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-3-concept-of-a-confidence-interval-and-its-interpretation/) — 23 question items · 16 papers — 75 marks · 2015–2026
- [3.4 Confidence limits for a Normal mean, with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-4-confidence-limits-for-a-normal-mean-with-variance-known/) — 30 question items · 18 papers — 123 marks · 2015–2026
- [3.5 Hypothesis tests for the mean of a Normal distribution with variance known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-5-hypothesis-tests-for-the-mean-of-a-normal-distribution-with-variance-known/) — 7 question items · 7 papers — 27 marks · 2016–2024
- [3.6 Use of Central Limit theorem to extend hypothesis tests and confidence intervals to samples from non-Normal distributions. Use of large sample results to extend to the case in which the variance is unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-6-use-of-central-limit-theorem-to-extend-hypothesis-tests-and-confidence-intervals/) — 38 question items · 19 papers — 96 marks · 2015–2026
- [3.7 Hypothesis test for the difference between the means of two Normal distributions with variances known.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-7-hypothesis-test-for-the-difference-between-the-means-of-two-normal-distributions/) — 18 question items · 14 papers — 103 marks · 2016–2026
- [3.8 Use of large sample results to extend to the case in which the population variances are unknown.](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/estimation-confidence-intervals-and-tests/3-8-use-of-large-sample-results-to-extend-to-the-case-in-which-the-population/) — 34 question items · 19 papers — 157 marks · 2014–2026

## Other topics in WST03

- [Combinations of random variables 62 question items](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/combinations-of-random-variables/)
- [Goodness of fit and contingency tables 92 question items](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/goodness-of-fit-and-contingency-tables/)
- [Regression and correlation 64 question items](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/regression-and-correlation/)
- [Sampling 42 question items](https://www.examsci.com/topics/edexcel-ial/mathematics/statistics-3-wst03/sampling/)

## Topic question rules and edge cases

**How many subtopics does Estimation, confidence intervals and tests contain?**

This page lists 8 subtopics tagged to the current syllabus. They are ordered by syllabus number, then alphabetically, and each row opens a page of matching past-paper questions.

**How are the subtopic question and mark totals calculated?**

A multiple-choice question contributes one item and its marks to every subtopic it is tagged with. A structured question contributes one item per tagged part, and that part’s marks; untagged parts of the same question are not counted here. A part tagged to several subtopics therefore appears under each of them.

**Why do some subtopics have no numbered prefix?**

Practical-skills statements and some syllabus bullets are unnumbered. Numbered statements come first; unnumbered statements and ties are sorted alphabetically.

**Is the LaTeX rendered without JavaScript?**

Yes. Subtopics that contain formulas are converted to static KaTeX HTML during the build, and the KaTeX stylesheet is served from the same site.

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