Quick jump
Chapter 1: Operations and Productivity
Single-Factor Productivity
Use when measuring output relative to one input type, such as labor hours or machine hours.
Multi-Factor Productivity
Input categories should use the same basis, usually dollars or another consistent cost unit.
Chapter 2: Operations Strategy in a Global Environment
Make-or-Buy Cost Comparison
Use this as a first-pass financial comparison. Strategic fit, quality, risk, capacity, and supplier reliability still matter.
Make-or-Buy Crossover Quantity
This applies when the buy cost per unit is higher than the internal variable cost. Above the crossover quantity, making internally may become cheaper.
Chapter 3: Project Management
PERT Expected Activity Time
a = optimistic time, m = most likely time, b = pessimistic time.
PERT Activity Variance
Crash Cost Slope
Use this to compare which crashable activities are cheapest to shorten first, while still respecting the critical path.
Chapter 4: Forecasting Accuracy
Mean Absolute Deviation (MAD)
Enter comma-separated values. Actual and forecast lists must have the same number of values.
Mean Squared Error (MSE)
Mean Absolute Percentage Error (MAPE)
MAPE requires every actual value to be greater than 0 because the formula divides by actual demand.
Chapter 5: Design of Goods and Services
Product-by-Value Contribution
Use this to prioritize products or services that contribute the most annual value.
Design Break-Even Quantity
Useful for comparing design alternatives or deciding whether expected volume can cover fixed design/setup cost.
Weighted Design Score
A simple helper for comparing design concepts against weighted criteria such as customer fit, manufacturability, cost, sustainability, and risk.
Chapter 6: Managing Quality
Process Capability Ratio (Cp)
Cp measures potential capability assuming the process is centered between specification limits.
Process Capability Index (Cpk)
Cpk accounts for whether the process mean is off-center.
Chapter 7: Process Strategy
Total Cost
Crossover Point
This finds the quantity where two cost alternatives are equal. Variable costs must be different.
Chapter 8: Location Strategies
Center of Gravity Method
Coordinate and weight lists must be the same length. Weights must not total zero.
Factor Rating Method
Weights may be decimals that sum to 1.0 or whole-number percentages that sum to 100.
Chapter 9: Layout Strategies
Total Work Distance
Takt Time
Supplemental: Inventory Formulas
These inventory helpers are preserved from the earlier checked calculator set. Depending on your course sequence, these may appear outside Chapters 1–9.
Economic Order Quantity (EOQ)
D = annual demand, S = ordering cost per order, H = annual holding cost per unit.
Reorder Point (ROP)
Leave safety stock blank if you want the basic deterministic reorder point.