Answer:
Operating income will decrease by $8282.
Step-by-step explanation:
Expected increase in revenues (85 x 320 ) $27,200
Less: expected increase in costs
Variable manufacturing (85 x 70.87*) 6,023.95
Variable selling & administrative (85 x 31.50**) 2,677.50
Additional fixed costs 20,000 28,701.45
Expected decrease in operating revenue $1,501
*Variable manufacturing cost per unit = 900,000 / 12,700 = $70.87
**Variable selling and administrative expenses per unit = 400,000 / 12,700 = $31.50