The table above shows information about patients at a medical clinic, categorized by age group and type of illness. If one of the patients is selected at random, what is the probability that the patient selected will be under 50 years old and have a major illness?
| Age Group | Minor Illness | Major Illness | Total |
|---|---|---|---|
| Under 50 | 12 | 6 | 18 |
| 50 or Over | 8 | 4 | 12 |
| Total | 20 | 10 | 30 |
