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Table 3.
Fuzzy sets to assess the questionnaires.
| Very poor | Poor | Fair | Good | Very good |
|---|---|---|---|---|
| (0, 0. 25) | (0,0.25, 0.5) | (0.25, 0.5, 0.75) | (0.5, 0.75, 1) | (0.75, 1) |