Racer Quadcopters plans to sell a standard quadcopter (toy drone) for $40 and a deluxe quadcopter for $60. Racer purchases the standard quadcopter for $30 and the deluxe quadcopter for $40. Management expects to sell two deluxe quadcopters for every three standard quadcopters. The company's monthly fixed expenses are $9,800. How many of each type of quadcopter must Racer sell monthly to breakeven? To earn $7,700? First identify the formula to compute the sales in units at various levels of operating income using the contribution margin approach. (Abbreviations used: Avg. = average, and CM = contribution margin.) ( Fixed expenses + Operating income ) - Weighed-avg. CM per unit = Breakeven sales in units Next compute the weighted-average contribution margin per unit. First identify the formula labels, then complete the calculations step by step. Standard $ 40 (30) Sale price per unit Deduct: Variable expense per unit Contribution margin per unit Sales mix in units $ 10 Contribution margin Weighted average contribution margin per unit