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Variable costs can include direct material costs or direct labor costs necessary to complete a certain project. For example, a company may have variable costs associated with the packaging of one of its products. As the company moves more of this product, the costs for packaging will increase.
Direct labor costs are the same as those used in prime cost calculations. Conversion costs are also used as a measure to gauge the efficiencies in production processes but take into account the overhead expenses left out of prime cost calculations.irect labor costs include the salary, wages or benefits paid to an employee who works on the completion of finished products. Compensation paid to machinists, painters or welders is common in calculating prime costs.