In: Operations Management
3. The Covington Paper Inc. would like to determine the location of its new DC which will serve their six manufacturing facilities in Midwest. Information is provided below.
| 
 Plants  | 
 x- coordinate  | 
 y coordinates  | 
 Production in terms of # of TLs /period  | 
| 
 A  | 
 6  | 
 20  | 
 220  | 
| 
 B  | 
 48  | 
 12  | 
 330  | 
| 
 C  | 
 25  | 
 36  | 
 560  | 
| 
 D  | 
 12  | 
 5  | 
 330  | 
| 
 E  | 
 30  | 
 50  | 
 225  | 
| 
 F  | 
 18  | 
 20  | 
 115  | 
i. Finding the optimal location using the median method
Step 1:
The x-coordinates are rearranged in ascending order in a table corresponding to the production of the location.
And the cumulative production is calculated.
| Plants | x coordinates in ascending order | Production of the plant | Cumulative production | 
| A | 6 | 220 | 220 | 
| D | 12 | 330 | 550 | 
| F | 18 | 115 | 665 | 
| C | 25 | 560 | 1125 | 
| E | 30 | 225 | 1450 | 
| B | 48 | 330 | 1780 = N | 
The median of the cumulative production can be found by N/2, (N/2)+1
N/2 = 890, (N/2)+1 = 891 these median values fall under the cumulative production range of 1125, therefore, the x-coordinate is 25.
Step 2:
The y-coordinates are rearranged in ascending order in a table corresponding to the production of the location.
And the cumulative production is calculated.
| Plants | y coordinates in ascending order | Production of the plant | Cumulative production | 
| D | 5 | 220 | 220 | 
| B | 12 | 330 | 550 | 
| A | 20 | 115 | 665 | 
| F | 20 | 560 | 1125 | 
| C | 36 | 225 | 1450 | 
| E | 50 | 330 | 1780 = N | 
The median of the cumulative production can be found by N/2, (N/2)+1
N/2 = 890, (N/2)+1 = 891 these median values fall under the cumulative production range of 1125, therefore, the y-coordinate is 20.
The optimal location by the median method is (25,20)
b. )
Solution:
the optimal location formula is
Xp = 
xPr / 
Pr
Yp = 
yPr / 
Pr
x is the x coordinate of the plant location
y is the y coordinate of the plant location
And Pr is the production of each plant
| Plants | x | y | Pr | xPr | yPr | 
| A | 6 | 20 | 220 | 1320 | 4400 | 
| B | 48 | 12 | 330 | 15840 | 3960 | 
| C | 25 | 36 | 560 | 14000 | 20160 | 
| D | 12 | 5 | 330 | 3960 | 1650 | 
| E | 30 | 50 | 225 | 6750 | 11250 | 
| F | 18 | 20 | 115 | 2070 | 2300 | 
 Pr
= 1780 | 
 xPr
= 43940 | 
 yPr
= 43720 | 
Xp = 
xPr / 
Pr
Xp = 43940 / 1780
Xp = 24.685
Yp = 
yPr / 
Pr
Yp = 43720 / 1780
Yp = 24.561
Therefore, the optimal location using center of gravity method is (24.685, 24.561)