Refer to Exercise 14. How many sweaters of each type should the company make in a day to get a maximum profit? What is the maximum profit?
Refer to Exercise 14. How many sweaters of each type should the company make in a day to get a maximum profit? What is the maximum profit?

Solution:

According to the solution of exercise 14,

NCERT Exemplar Solutions Class 12 Mathematics Chapter 12 - 15

we have Maximize Z=200 x+120 y subject to constrains

\begin{array}{l} 3 x+y \leq 600 \ldots \text { (i) } \\ x+y \leq 300 \ldots \text { (ii) } \\ x-y \leq-100 \ldots \text { (iii) } \\ x \geq 0, y \geq 0 \end{array}

Let’s construct a constrain table for the above

Table for (i)

    \[\begin{tabular}{|l|l|l|} \hline $\mathrm{x}$ & 0 & 200 \\ \hline $\mathrm{y}$ & 600 & 0 \\ \hline \end{tabular}\]

Table for (ii)

    \[\begin{tabular}{|l|l|l|} \hline $\mathrm{x}$ & 0 & 300 \\ \hline $\mathrm{y}$ & 300 & 0 \\ \hline \end{tabular}\]

Table for (iii)

    \[\begin{tabular}{|l|l|l|} \hline $\mathrm{x}$ & $-100$ & 0 \\ \hline $\mathrm{y}$ & 0 & 100 \\ \hline \end{tabular}\]

On solving (i) and (ii), we obtain x=150 and y=150

It can be seen that the shaded region is the feasible region whose corner points are \mathrm{O}(0,0), \mathrm{A}(200,0), \mathrm{B}(150, 150), \mathrm{D}(0,100).

Evaluating the value of Z, we have

    \[\begin{tabular}{|l|l|} \hline Corner points & Value of $\mathrm{Z}=2000 \mathrm{x}+120 \mathrm{y}$ \\ \hline $0(0,0)$ & $\mathrm{Z}=200(0)+120(0)=0$ \\ \hline $\mathrm{A}(200,0)$ & $\mathrm{Z}=200(200)+120(0)=40000$ \\ \hline $\mathrm{B}(150,150)$ & $\mathrm{Z}=200(150)+120(150)=48000$ \\ \hline $\mathrm{C}(100,200)$ & $\mathrm{Z}=200(100)+120(200)=44000$ \\ \hline $\mathrm{D}(0,100)$ & $\mathrm{Z}=200(0)+120(100)=12000$ \\ \hline \end{tabular}\]

It is seen from the above table that the maximum value is 48000 .

So, the maximum value of \mathrm{Z} is 48000 at (150,150) which means 150 sweaters of each type.