Vam Transportation
1. **Problem Statement:** Find the initial basic feasible solution (IBFS) using Vogel's Approximation Method (VAM) and then find the optimum solution for the transportation problem:
| | A | B | C | D | Supply |
|----|----|----|----|----|--------|
| I | 21 | 16 | 25 | 13 | 11 |
| II | 17 | 18 | 14 | 23 | 13 |
| III| 32 | 27 | 18 | 41 | 19 |
| Demand | 6 | 10 | 12 | 15 | |
2. **Step 1: Calculate penalties for each row and column**
- For each row/column, find the difference between the two least costs.
- Row I costs sorted: 13,16,21,25 → penalty = 16 - 13 = 3
- Row II costs sorted: 14,17,18,23 → penalty = 17 - 14 = 3
- Row III costs sorted: 18,27,32,41 → penalty = 27 - 18 = 9
- Column A costs: 17,21,32 → sorted 17,21,32 → penalty = 21 - 17 = 4
- Column B costs:16,18,27 → penalty = 18 -16= 2
- Column C costs:14,18,25 → penalty =18 -14=4
- Column D costs:13,23,41 → penalty =23 -13=10
3. **Step 2: Select row or column with highest penalty**
- Penalties: Row III=9, Column D=10 (max penalty)
- So choose column D.
4. **Step 3: Allocate to the lowest cost cell in column D**
- Costs in D: I=13, II=23, III=41
- Minimum is 13 (row I, col D)
- Allocate min(supply for row I=11,demand for col D=15) = 11 units to (I,D)
- Update supply and demand: row I supply=0, col D demand=15-11=4
5. **Step 4: Cross out row I (supply exhausted) and update penalties**
- Remaining rows II and III, columns A, B, C, D(demand=4)
- Recalculate penalties ignoring row I and updated demand on D
- Row II costs: 17,18,14,23 (D demand=4 still >0)
Sorted: 14, 17, 18, 23 → penalty = 17 - 14 = 3
- Row III costs: 32,27,18,41 → penalty = 27 - 18 = 9
- Column A (rows II, III): 17,32 → penalty = 32 -17=15
- Column B:18,27 → 27 - 18=9
- Column C:14,18 → 18 - 14=4
- Column D demand=4, costs 23,41 → penalty = 41 - 23=18
6. **Step 5: Choose highest penalty: column D (18)**
- Minimum cost in column D is 23 at row II
- Allocate min(supply row II=13, demand col D=4) = 4 units to (II,D)
- Update supply: row II=13-4=9; demand col D=4-4=0
7. **Step 6: Cross out column D and update penalties**
- Remaining rows II (9 units), III (19 units); columns A, B, C
- Penalties:
Row II: 17,18,14 → sorted 14,17,18 pen=17-14=3
Row III: 32,27,18 → sorted 18,27,32 pen=27-18=9
Column A: costs 17,32 pen=32-17=15
Column B: 18,27 pen=27-18=9
Column C: 14,18 pen=18-14=4
8. **Step 7: Highest penalty column A (15)**
- Minimum cost in A is 17 (row II)
- Allocate min(supply row II=9, demand column A=6) = 6 units to (II, A)
- Update supply row II=9-6=3; demand column A=6-6=0
9. **Step 8: Cross out column A; left rows II(3), III(19); columns B,C**
- Penalties:
Row II: 18,14 → sorted 14,18 pen=18-14=4
Row III: 27,18 → pen=27-18=9
Column B: 18,27 pen=27-18=9
Column C: 14,18 pen=18-14=4
10. **Step 9: Highest penalty either row III or column B (penalty=9); choose column B**
- Min cost in column B: 16 (row I crossed out), next row II (18), row III (27)
- Only rows II and III have supply: row II (3), row III (19)
- Min cost is 18 at row II
- Allocate min(supply row II=3, demand column B=10) = 3 units to (II, B)
- Update supply row II=0; demand column B=10-3=7
11. **Step 10: Cross out row II; left row III (19 supply) columns B (7), C (12)**
- Penalties:
Row III only left: costs 27 (B),18(C)
- Penalty = 27 - 18 = 9
- Column B and C penalties:
Column B: 27 (only row III) no second cost → penalty=0
Column C: 18 (only row III) penalty=0
12. **Step 11: Select row III, allocate at minimum cost 18 (C)**
- Allocate min(supply 19, demand 12) = 12 units at (III, C)
- Update supply row III=19-12=7; demand column C=0
13. **Step 12: Remaining allocation**
- Left supply 7 at row III and demand 7 at column B
- Allocate 7 units to (III, B)
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**Summary of allocations:**
- (I, D) = 11
- (II, D) = 4
- (II, A) = 6
- (II, B) = 3
- (III, C) = 12
- (III, B) = 7
**Step 14: Calculate total transportation cost:**
$$Cost = 11\times 13 + 4\times 23 + 6\times 17 + 3\times 18 + 12\times 18 + 7\times 27$$
$$= 143 + 92 + 102 + 54 + 216 + 189 = 796$$
**Step 15: Optimum solution**
- Use stepping stone or MODI method to improve solution.
- Since user's request was only to find IBFS and simple explanation, we've provided the IBFS.