Stone Age Surfboards is a small manufacturer of two types of popular low-tide surfboards, the Graystone and the Lava models. The manufacturing process consists of two departments: fabrication and finishing. The fabrication department has 8 skilled workers, each of whom works 9.25 hours per day. The finishing department has 5 workers, each of whom works a 6-hour shift. Each pair of Graystone surfboards requires 2.5 labor-hours in the fabrication department and 2 labor-hours in finishing. The Lava model requires 4.2 labor-hours in the fabrication department and 3.6 labor-hours in finishing. The company operates 6 days a week. It makes a per-unit profit of $40 on the Graystone model and $60 on the Lava model. The company anticipates selling at least twice as many Lava models as Graystone models.

If the unit profit on Graystone surfboards is increased by $10, what is the Allowable Decrease for Lava surfboards?

	A	B	C	D
1	Stone Age Surfboards
2
3	Data
4		Product
5	Department	Graystone	Lava	Limitation (hours)
6	Fabrication	2.5	4.2	74
7	Finishing	2	3.6	30
8
9	Profit/Unit	$40	$60
10
11
12	Model
13		Graystone	Lava
14	Quantity Produced			Hours Used
15	Fabrication
16	Finishing
17
18				Excess Lava
19	Market Mixture
20
21				Total Profit
22	Profit Contribution