Furniture Production
1. **State the problem:**
We want to maximize the profit from producing tables (x) and chairs (y) given constraints on available hours in two departments.
2. **Formulate the objective function:**
The profit per table is 30 and per chair is 24. So, the objective function to maximize is:
$$Z = 30x + 24y$$
3. **Formulate the constraints:**
Department 1 hours: Producing one table takes 3 hours and one chair takes 6 hours, total hours available is 120:
$$3x + 6y \leq 120$$
Department 2 hours: Producing one table takes 6 hours and one chair takes 3 hours, total hours available is 96:
$$6x + 3y \leq 96$$
Non-negativity constraints:
$$x \geq 0, \quad y \geq 0$$
4. **Graph the constraints:**
- For $$3x + 6y = 120$$, intercepts are:
- When $$x=0$$, $$y=20$$
- When $$y=0$$, $$x=40$$
- For $$6x + 3y = 96$$, intercepts are:
- When $$x=0$$, $$y=32$$
- When $$y=0$$, $$x=16$$
5. **Determine the feasible region:**
The feasible region is the area where both inequalities hold, including the axes (since $$x,y \geq 0$$). It is bounded by the lines and axes.
6. **Find corner points of the feasible region:**
- Intersection with axes:
- (0,0)
- (0,16) from $$6x+3y=96$$ when $$x=0$$
- (20,0) from $$3x+6y=120$$ when $$y=0$$
- Intersection of the two lines:
Solve system:
$$3x + 6y = 120$$
$$6x + 3y = 96$$
Multiply first by 1 and second by 2:
$$3x + 6y = 120$$
$$12x + 6y = 192$$
Subtract first from second:
$$12x + 6y - (3x + 6y) = 192 - 120$$
$$9x = 72 \Rightarrow x = 8$$
Substitute $$x=8$$ into first equation:
$$3(8) + 6y = 120 \Rightarrow 24 + 6y = 120 \Rightarrow 6y = 96 \Rightarrow y = 16$$
So intersection point is (8,16).
7. **Evaluate objective function at corner points:**
- At (0,0): $$Z=0$$
- At (0,16): $$Z=30(0)+24(16)=384$$
- At (20,0): $$Z=30(20)+24(0)=600$$
- At (8,16): $$Z=30(8)+24(16)=240+384=624$$
8. **Decision:**
Maximum profit is $$624$$ at $$x=8$$ tables and $$y=16$$ chairs.
Hence, the optimal production plan is to produce 8 tables and 16 chairs to maximize profit.