# WDM11/01 October 2020

> WDM11/01 October 2020: 8 questions, 75 marks. Difficulty 0.45, deviation 0.19, algebraic 0.29, text density 0.39. Edexcel IAL Mathematics D1.

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Edexcel IAL · Mathematics · 2020 October

This Decision Mathematics 1 (WDM11) paper contains 8 questions worth 75 marks. The profile below reports five mark-weighted difficulty and complexity measures, and every question row repeats them. Full question text and mark scheme open in the Interactive Practice Hub.

- Edexcel IAL
- D1
- 8 questions
- 75 marks
- Free paper
- [Practise this paper](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf)
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Core finding

**WDM11/01 October 2020 is a past paper for Edexcel IAL Decision Mathematics 1 (WDM11), with 8 questions worth 75 marks.** Its mark-weighted Difficulty Measure is 0.45 on a 0.20–0.75 scale, with a Difficulty Deviation of 0.19 and a mark split of 22.7% Easy, 48.0% Medium and 29.3% Hard. Algebraic complexity averages 0.29; text density and modelling average 0.39. All five measures use 25 part-level tags, not candidate results. Every question row below repeats them and opens the Interactive Practice Hub for that question.

## Difficulty & complexity profile

All five measures are mark-weighted and calculated from 25 parts carrying 75 part marks. Difficulty tags cover 25 parts, algebraic tags 25 and text-density tags 25. Tags are internal metadata, not official exam-board ratings.

- **Difficulty Measure**: 0.45 — 0.20–0.75 · nearer Medium
- **Difficulty Deviation**: 0.19 — 0 = uniform; higher = more mixed
- **Difficulty Ratio**: 22.7 / 48.0 / 29.3 — % Easy / Medium / Hard
- **Algebraic Complexity Measure**: 0.29 — 0.20–0.75 · nearer Low
- **Text Density and Modelling Measure**: 0.39 — 0.20–0.75 · nearer Medium

Scale: Easy 0.20 · Medium 0.45 · Hard 0.75, and Low 0.20 · Medium 0.45 · High 0.75 for the two complexity measures. [How each band is defined and how the values are calculated →](https://www.examsci.com/guides/difficulty-and-complexity-measures/)

### Definitions and calculation

| Measure | Paper value | Formula |
| --- | --- | --- |
| **Difficulty Measure** | 0.45 | Σ(d_i × w_i) / Σw_i, with d = 0.20 / 0.45 / 0.75 |
| **Difficulty Deviation** | 0.19 | √(Σw_i(d_i − μ)^2 / Σw_i) |
| **Difficulty Ratio** | 22.7% Easy / 48.0% Medium / 29.3% Hard | marks in band / all tagged marks |
| **Algebraic Complexity Measure** | 0.29 | Σ(c_i × marks_i) / Σmarks_i, with c = 0.20 / 0.45 / 0.75 |
| **Text Density and Modelling Measure** | 0.39 | Σ(t_i × marks_i) / Σmarks_i, with t = 0.20 / 0.45 / 0.75 |

w_i equals the part marks, except for a Hard part worth 4 or more marks, where w_i = marks^0.75 to offset the accessible starter steps inside long structured questions.

## Question list

Each measure is recalculated from the parts of that question and uses the same weights as the paper profile.

| Question | Topic | Marks | Difficulty Measure | Algebraic Complexity Measure | Text Density and Modelling Measure | Practice |
| --- | --- | --- | --- | --- | --- | --- |
| **Q1** FRQ | [2. Algorithms on graphs](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/algorithms-on-graphs/) | 7 | 0.31 Easy | 0.20 Low | 0.20 Low | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=265e5105-947b-48f9-89e7-211522debd4b&source_detail=WDM11%2F01+October+2020) |
| **Q2** FRQ | [1. Algorithms](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/algorithms/) | 13 | 0.37 Medium | 0.20 Low | 0.24 Low | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=7799bd0a-b936-4dd7-b293-dbd22d02f3af&source_detail=WDM11%2F01+October+2020) |
| **Q3** FRQ | [3. Algorithms on graphs II](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/algorithms-on-graphs-ii/) | 7 | 0.38 Medium | 0.20 Low | 0.38 Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=332ddccc-6518-4bb6-bb90-35a7bdd2ab5d&source_detail=WDM11%2F01+October+2020) |
| **Q4** FRQ | [4. Critical path analysis](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/critical-path-analysis/) | 7 | 0.45 Medium | 0.20 Low | 0.20 Low | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=87cba8ea-73cd-4dae-8835-584b9602e521&source_detail=WDM11%2F01+October+2020) |
| **Q5** FRQ | [4. Critical path analysis](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/critical-path-analysis/) | 12 | 0.38 Medium | 0.20 Low | 0.37 Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=5200ad1e-c764-4aff-b7a7-dc401b14682f&source_detail=WDM11%2F01+October+2020) |
| **Q6** FRQ | [5. Linear programming](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/linear-programming/) | 7 | 0.64 Hard | 0.45 Medium | 0.38 Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=45563aa2-19ee-49a9-85ac-82ad9311b9eb&source_detail=WDM11%2F01+October+2020) |
| **Q7** FRQ | [2. Algorithms on graphs](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/algorithms-on-graphs/) | 11 | 0.75 Hard | 0.45 Medium | 0.56 Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=7d14410c-afc1-41eb-b76f-b4aa835dec90&source_detail=WDM11%2F01+October+2020) |
| **Q8** FRQ | [5. Linear programming](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/linear-programming/) | 11 | 0.51 Medium | 0.43 Medium | 0.70 High | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c25b7eef-6a17-4099-ae04-28b44359a5bf&question_id=b1db4af1-6ea8-4a6d-bb81-cf8b9a82c6e9&source_detail=WDM11%2F01+October+2020) |

## Topics in this paper

- [2. Algorithms on graphs](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/algorithms-on-graphs/)
- [1. Algorithms](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/algorithms/)
- [3. Algorithms on graphs II](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/algorithms-on-graphs-ii/)
- [4. Critical path analysis](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/critical-path-analysis/)
- [5. Linear programming](https://www.examsci.com/topics/edexcel-ial/mathematics/decision-mathematics-1-wdm11/linear-programming/)

## Related papers

- [WDM11/01](https://www.examsci.com/past-papers/edexcel-ial/mathematics/decision-mathematics-1-wdm11/2020-january-wdm11-01/) — January 2020 — 7 questions · 75 marks — Free
- [WDM11/01](https://www.examsci.com/past-papers/edexcel-ial/mathematics/decision-mathematics-1-wdm11/2021-october-wdm11-01/) — October 2021 — 7 questions · 75 marks — Pro
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- [WDM11/01](https://www.examsci.com/past-papers/edexcel-ial/mathematics/decision-mathematics-1-wdm11/2022-june-wdm11-01/) — June 2022 — 7 questions · 75 marks — Pro

## Paper FAQ

**How are the difficulty and complexity measures calculated?**

Each part is weighted by its official marks. Difficulty uses Easy 0.20, Medium 0.45 and Hard 0.75; algebraic complexity and text density and modelling use Low 0.20, Medium 0.45 and High 0.75. A Hard part worth 4 or more marks is down-weighted to marks^0.75, so the accessible starter steps inside a long structured question do not inflate the difficulty result. This paper's Difficulty Measure is 0.45 from 25 parts.

**What does the Difficulty Deviation show?**

It is the mark-weighted standard deviation of the part difficulty values around the paper mean. A value of 0 would mean every tagged part has the same difficulty; this paper's deviation is 0.19, so its parts are more mixed than a single-level paper.

**Is the Difficulty Ratio based on question counts or marks?**

It is based on official marks, not question counts. This paper's shares are 22.7% Easy, 48.0% Medium and 29.3% Hard; the three shares sum to 100% before rounding.

**Are these official difficulty ratings?**

No. They are derived from the platform's part-level difficulty and static-question-profile tags. They are not exam-board grade boundaries and are not calculated from candidate outcomes. Use them to compare the demand profile of papers, not to predict a grade.

**Why does each question row show its own measures?**

Each row recalculates the same mark-weighted formula from that question's parts. A single-part MCQ therefore shows the tag value directly, while a multi-part structured question blends the tags of its parts using the same Hard-part decay as the paper profile.

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Full page with native tables, bar charts and Practice Hub links: https://www.examsci.com/past-papers/edexcel-ial/mathematics/decision-mathematics-1-wdm11/2020-october-wdm11-01/