Week 4 — Managing quality
Thursday, 22 October 2026 · Heizer Ch. 6 + S6
ChapterHeizer Ch. 6 — Managing quality; S6 Statistical process control
Morning testT2 · calculations from Weeks 2–3 (Ch. 7, S7, S5) + two Chapter 1 calculations
Bonus sheetcounts toward T3
Group projectcheck cell (automatic data test) and animation template released
Times09:00–12:00 · 13:00–15:30
Test 2 preparation
When and how. Thursday, 22 October, 09:00. First alone (iRAT), then the same questions in your team (gRAT). On paper, calculator allowed, phones and books closed; your code name on the answer sheet; write the calculation path in the boxes.
What Test 2 asks: calculations. Four kinds, as practised in class and on the bonus sheets, with new numbers:
- Crossover charts. Total cost = fixed cost + variable cost per unit × volume, one line per option; the crossover is where two lines cross: difference in fixed cost ÷ difference in variable cost. You use it twice:
- Process types (Ch. 7): which process (process focus, repetitive, product focus) is cheapest at which volume; break-even volume = fixed cost ÷ (price − variable cost per unit)
- Vehicles and equipment (S5): the crossover in km, and in years = km ÷ km per year
- Life cycle cost (S5, Equation S5-2): purchase price + energy cost per km × km per year × years + other operating cost per km × km per year × years; which option is cheaper over its life
- Carbon footprint: Σ amount × emission factor, stage by stage, with the amount in the factor’s unit (kg, kWh, tonne-km); the share of the biggest stage; the hotspot
- Process efficiency and capacity (Ch. 7 + S7), as on the Week 2 bonus sheet: design and effective capacity; utilization = actual ÷ design; efficiency = actual ÷ effective; capacity of each step, bottleneck, line output, throughput time; people or machines needed (round up); the bottleneck of a supply chain
You should be able to draw a crossover chart by hand and read the cheapest option for a given volume or distance from it.
The Backhaus Kaya case is test content. The calculations of both parts of the case are part of Test 2, with new numbers:
- Part 1 (Week 2): the oven’s design and effective capacity, utilization and efficiency; the bottleneck of the night shift; the crossover of the current process and the roll line, and the break-even volume of the contract; the capacity of the chain flour mill → bakery → van
- Part 2, “The carbon clause” (Week 3): the footprint of one roll by stage and its hotspot; the life cycle cost and crossover of the two vans; round trips and crates (round up); cost per tonne avoided and the cheapest-first plan for the contract target
Work through your printed case and your team’s answers again; the Week 2 key content and the Colab notebooks of Weeks 2 and 3 use the same numbers.
Plus two small Chapter 1 calculations: your learning path. Every paper carries two short calculations of the kinds you met in Test 1: multifactor productivity (turn every input into € before you add) and people needed (apply the demand change first, then round up). This is your second chance at Chapter 1. Practise with the Week 1 exercises and your Test 1 feedback sheet.
Read. Supplement 5, Chapter 7 and Supplement 7 of Heizer et al. (2023), with their case studies: Orlando Magic’s Amway Center, Frito-Lay and Celebrity Cruises (S5), and Arnold Palmer Hospital (S7). Work through the discussion questions of every case; questions on the cases are possible. Chapter 5 itself is not tested.
Practise. Week 2 exercises · Week 3 exercises (footprint, life cycle cost and cost per tonne, with answers) · Solved Problem S5.2 and Example S2 · the one-page formula sheets: Week 1 (for the two Chapter 1 calculations), Week 2, Week 3.
Bonus. The Week 2 bonus sheet (written on 15 October) counts toward Test 2: if it counts, it makes a passed Test 2 grade 0.3 better (Assessment).
The full page — the problem of the week, the exercises and the downloads — opens soon. Until then, prepare for Test 2 and read Chapter 6.