- Practice · 6 marks
Weighted factor rating for choosing a site
Short answer
Multiply each factor weight by the site score and sum; the site with the highest total weighted score is best. Site C has the highest weighted score (7.21) compared to A (6.92) and B (6.71), so select site C.
A company has shortlisted three sites A, B and C for a new plant. The management gives the weights and scores each site out of 10 as follows. Select the best site using the weighted factor rating method.
| Factor | Weight | Site A | Site B | Site C |
|---|---|---|---|---|
| Raw material availability | 0.25 | 8 | 6 | 7 |
| Labour cost and skill | 0.20 | 6 | 8 | 7 |
| Nearness to market | 0.20 | 7 | 5 | 8 |
| Power and water | 0.15 | 8 | 7 | 6 |
| Transport facilities | 0.12 | 6 | 7 | 9 |
| Taxes and government support | 0.08 | 5 | 9 | 6 |
Method
In the weighted factor rating method, each factor is given a weight (sum = 1.00) and each site is scored. The weighted score is , and the site with the largest total is selected. The weights add to , so the totals are directly comparable.
Calculation
| Factor | Weight | A | B | C |
|---|---|---|---|---|
| Raw material | 0.25 | 0.25x8 = 2.00 | 0.25x6 = 1.50 | 0.25x7 = 1.75 |
| Labour | 0.20 | 0.20x6 = 1.20 | 0.20x8 = 1.60 | 0.20x7 = 1.40 |
| Market | 0.20 | 0.20x7 = 1.40 | 0.20x5 = 1.00 | 0.20x8 = 1.60 |
| Power and water | 0.15 | 0.15x8 = 1.20 | 0.15x7 = 1.05 | 0.15x6 = 0.90 |
| Transport | 0.12 | 0.12x6 = 0.72 | 0.12x7 = 0.84 | 0.12x9 = 1.08 |
| Taxes, support | 0.08 | 0.08x5 = 0.40 | 0.08x9 = 0.72 | 0.08x6 = 0.48 |
| Total | 1.00 | 6.92 | 6.71 | 7.21 |
Decision
Site C has the highest weighted score (7.21), then A (6.92) and B (6.71). Site C is selected. The margin over A is small (0.29), so the result should be checked for sensitivity, e.g. by changing the weight of the raw-material factor, because the weights are subjective.
Answer: Site C, weighted score 7.21 (A = 6.92, B = 6.71).
✓ Answer checked by Claude Opus 5.5 (high effort)
Related questions
- Break-even cost comparison of three sites · Industrial Engineering and Management, chapter 2
- Flow patterns in plant layout · Industrial Engineering and Management, chapter 2
- Material handling objectives and principles · Industrial Engineering and Management, chapter 2
- Forecasting by moving average and smoothing · Industrial Engineering and Management, chapter 6
- Importance and factors of plant location · Industrial Engineering and Management, chapter 2
- Repeatability assumption, select best of three projects · Engineering Economics, chapter 4 · asked 2×
- ERR method to select best of three projects · Engineering Economics, chapter 4
- Best of three mutually exclusive projects, 10-year study · Engineering Economics, chapter 4
- Entrance scores of three institutes · Probability and Statistics, chapter 1 · asked 2×
All Industrial Engineering and Management chapter 2 questions →