Optimization- whose goal is to find the max or min value in a given function

Question: Accenter Industries Limited (AIL) uses high grade odum and sapele wood to produce chairs, tables and cupboards for schools. The target for the company is to produce at least 150 chairs, 200 tables and 60 cupboards. Over the years, AIL has established that each ton of odum wood yields 3 chairs 5 tables and 3 cupboards. On the other hand each ton sapele wood produces 5 chairs, 5 tables and a cupboard. A ton of odum and sapele cost $40 and $50 respectively. What combination of chairs tables and cupboards should AIL produce to minimize cost of production?

Hint: Let x represent a ton of odum wood
Let y represent a ton of sapele wood.