Final answer:
Lean Costing uses Value Stream Costing to manage costs, focusing on value creation and waste reduction, unlike Standard Costing, Departmental Budgetary Variance, and Activity-Based Costing.
Step-by-step explanation:
The variance analysis method that Lean Costing would primarily use is Value Stream Costing. Lean Costing focuses on the costs associated with a product's entire lifecycle or value stream rather than the traditional departmental or activity-based approaches. Traditional costing methods like Standard Costing, Departmental Budgetary Variance, and Activity-Based Costing may not align as closely with the principles of Lean, which emphasize waste reduction and value creation from the customer's perspective. By understanding the breakdown into fixed cost, marginal cost, average total cost, and average variable cost, businesses can gain insights that are crucial for making strategic decisions to enhance their value streams and reduce waste.