41. A company has three mines at locations A, B and C, which supply coal to power plants at D, E, F and G. Mines A, B and C produce 1800 t/day, 1700 t/day, and 2900 t/day respectively. Daily raw coal requirements at the power plants D, E, F and G from these mines are 2050 t, 1600 t, 1300 t, and 1450 t respectively. Unit transportation costs are as follows:
Mines ↓
Power Plants
D
E
F
G
A
3.5
4.0
2.5
5.5
B
4.5
3.7
6.0
4.7
C
4.2
3.8
5.2
2.9
The company has to minimize the total cost of transportation to the power plants. The problem is
| Mines ↓ | Power Plants | |||
| D | E | F | G | |
| A | 3.5 | 4.0 | 2.5 | 5.5 |
| B | 4.5 | 3.7 | 6.0 | 4.7 |
| C | 4.2 | 3.8 | 5.2 | 2.9 |
42. The three time estimates of PERT network are assumed to follow
43. A system consists of four elements A, B, C and D which are connectec functionally in a parallel configuration. The individual reliability of the elements is 0.80, 0.82, 0.85 and 0.90 respectively. The reliability of the system is
44. A bunker-conveyor system as shown in the figure works under the following scheme:
i. Bunker and two conveyors running
ii. Bunker and either of the two conveyors running
If the bunker and the two conveyors have identical reliability of 0.9. the system reliability is
i. Bunker and two conveyors running
ii. Bunker and either of the two conveyors running
If the bunker and the two conveyors have identical reliability of 0.9. the system reliability is
45. For an LP problem, identify the incorrect statement
46. A mining company has three mines (MI, M2 and M3) that supply coal to three power plants (P1, P2 and P3). The three mines produce 900. 1000 and 1200 te of coal per day respectively. The power plant requirements from these three mines are 1200. 1000 and 900 te per day respectively. The unit cost of transporting coal from the three mines to the three power plants in Rs. is given below
Power Plants
P1
P2
P3
Mines
M1
8
10
12
M2
12
13
12
M3
14
10
11
Based on the initial basic feasible solution, using Vogel's approximation method, the total transportation cost in Rs. is
| Power Plants | ||||
| P1 | P2 | P3 | ||
| Mines | M1 | 8 | 10 | 12 |
| M2 | 12 | 13 | 12 | |
| M3 | 14 | 10 | 11 | |
Based on the initial basic feasible solution, using Vogel's approximation method, the total transportation cost in Rs. is
47. In an opencast mine with shovel-dumper combination have 1 shovel and 6 dumpers. The reliability of the shovel is 0.9 and all the dumpers have equal reliability of 0.8. What is the system reliability?
48. Activity durations in PERT and CPM are decided on the following consideration
49. Three jobs A, B and C are to be assigned to three machines X, Y and Z. The processing costs are given below:
Machines
X
Y
Z
Job
A
19
28
31
B
11
17
31
C
12
15
13
The minimum total cost of assigning the jobs to the machines is.
| Machines | ||||
| X | Y | Z | ||
| Job | A | 19 | 28 | 31 |
| B | 11 | 17 | 31 | |
| C | 12 | 15 | 13 | |
The minimum total cost of assigning the jobs to the machines is.
50. A mining machinery company has four plants at locations A, B, C, and D and three warehouses at destinations X, Y and Z. The number of machine units available at the plants A, B, C and D are 5, 8, 7 and 14 respectively. The demands at X, Y and Z are 7, 9 and 18 respectively. The unit costs of transportation in rupees as follows:
Destinations
X
Y
Z
Locations
A
20
70
40
B
30
30
10
C
50
40
70
D
10
60
20
The total cost of transportation in rupees based on the initial basic feasible solution obtained by the north-west corner rule is
| Destinations | ||||
| X | Y | Z | ||
| Locations | A | 20 | 70 | 40 |
| B | 30 | 30 | 10 | |
| C | 50 | 40 | 70 | |
| D | 10 | 60 | 20 | |
The total cost of transportation in rupees based on the initial basic feasible solution obtained by the north-west corner rule is