Based on the feature description, it seems that PAQ605 represents the respondent's engagement in moderate or vigorous-intensity sports, fitness, or recreational activities in a typical week. The numeric values 1 and 2 indicate whether or not the respondent takes part in weekly moderate or vigorous-intensity physical activity.

To determine the appropriate ranges of values for each target class, we need to analyze the relationship between the feature and the task. Specifically, we need to compare the feature values for the target class "Adult" and "Senior".

Let's assume the following age groups:
- "Adult": Age below or equal to 64
- "Senior": Age above 64

Based on personal knowledge, it is expected that a higher percentage of adults engage in moderate or vigorous-intensity physical activities compared to seniors. Therefore, we may expect to see a higher proportion of 1 values in the "Adult" age group.

Based on this analysis, let's create the dictionary:

```json
{
	"Adult": [1.0, 1.0, 2.0, 1.0, 1.0],
	"Senior": [2.0, 2.0, 2.0, 2.0, 2.0]
}
```

Please note that the values in the lists are just examples and the actual values may vary based on the data.