Let godown A supply x quintals and y quintals of grain to the shops D and E respectively.
Then, (100 - x - y) will be supplied to shop F.
The requirement at shop D is 60 quintals since, x quintals are transported from godown A.
Therefore, the remaining (60 - x) quintals will be transported from godown B.
Similarly, (50 - y) quintals and 40 - (100 - x - y) i.e. (x + y - 60) quintals will be transported from godown B to shop E and F respectively.
The given problem can be represented diagrammatically as follows.

Quantity of the grain cannot be negative.
Therefore, x ≥ 0, y ≥ 0, and 100 - x - y ≥ 0
x ≥ 0, y ≥ 0, and x + y ≤ 100
60 - x ≥ 0, 50 - y ≥ 0, and x + y - 60 ≥ 0
x ≤ 60, y ≤ 50, and x + y ≥ 60
Total transportation cost Z is given by,
Z = 6x + 3y + 2.5 (100 - x - y) + 4(60 - x) + 2(50 - y) + 3(x + y - 60)
= 6x + 3y + 250 - 2.5x - 2. 5y + 240 - 4x + 100 - 2y + 3x + 3y - 180
= 2.5x + 1. 5y + 410
The given problem can be formulated as:
Minimize Z = 2.5x + 1.5y + 410
Subject to the constraints,
x + y ≤ 100
X ≤ 60
y ≤ 50
x + y ≥ 60
x, y ≥ 0
First we will convert inequations into equations as follows:
x + y = 100, x = 60, y = 50, x + y = 60, x = 0 and y = 0
Region represented by x + y ≤ 100:
The line x + y = 100 meets the coordinate axes at A1(100, 0) and B1(0, 100) respectively.
By joining these points we obtain the line x + y = 100.
Clearly (0, 0) satisfies the x + y ≤ 100.
So, the region which contains the origin represents the solution set of the inequation
x + y ≤ 100.
Region represented by x ≤ 60:
x = 60 is the line that passes (60, 0) and is parallel to the y-axis.
The region to the left of the line x = 60 will satisfy the inequation x ≤ 60.
Region represented by y ≤ 50:
y = 50 is the line that passes (0, 50) and is parallel to the x-axis.
The region below the line y = 50 will satisfy the inequation y ≤ 50.
Region represented by x + y ≥ 60:
The line x + y= 60 meets the coordinate axes at C1(60, 0) and D1(0, 60) respectively.
By joining these points we obtain the line x + y = 60.
Clearly (0, 0) does not satisfies the inequation x + y ≥ 60.
So, the region which does not contain the origin represents the solution set of the inequation x + y ≥ 60.
Region represented by x ≥ 0 and y ≥ 0:
Since, every point in the first quadrant satisfies these inequations.
So, the first quadrant is the region represented by the inequations x ≥ 0, and y ≥ 0.
The feasible region determined by the system of constraints x + y ≤ 100, x ≤ 60, y ≤ 50, x + y ≥ 60, x ≥ 0 and y ≥ 0 are as follows.

The corner points are C1(60, 0), G1(60, 40), F1(50, 50), and E1(10, 50).
The values of Z at these corner points are as follows:
| Corner point | Z = 2.5x + 1.5y + 410 |
| C1(60, 0) | 560 |
| G1(60, 0) | 620 |
| F1(50, 5) | 610 |
| E1(10, 0) | 510 |
The minimum value of Z is 510 at E1(10, 50).
Thus, the amount of grain transported from A to D, E, and F is 10 quintals, 50 quintals, and 40 quintals respectively and from B to D, E, and F is 50 quintals, 0 quintals, and 0 quintals respectively.
The minimum cost is Rs. 510.