Problem
Two models of a product - Regular (X) and Deluxe (Y) - are produced by a company. A linear programming model is used to determine the production schedule. The formulation is as follows:
Maximise profit 50X + 60Y
Subject to: 8X + 10Y <= 800 (labour hours)
X + Y <= 120 (total units demanded)
4X + 5Y <= 500 (raw materials)
all variables >= 0
IF the optimal solution is X = 100 Y = 0, how many units of the labour hours must be used to produce this number of units?