Based on the given feature description, LBXGLT represents the respondent's oral health status. To determine the appropriate ranges of values, we can use our prior knowledge and intuition about oral health.

For the task of predicting the age group, we can assume that seniors might have higher LBXGLT values compared to non-seniors. Senior individuals usually face oral health issues, such as gum diseases, dental decay, and tooth loss, due to aging and other related factors. Therefore, we can expect higher LBXGLT values for seniors.

To create the dictionary, we will assume the age group of 65 and above as the cutoff for the senior category. We will use this age cutoff to determine the appropriate ranges of values for LBXGLT.

Here is the dictionary with LBXGLT values for the target classes:

```json
{
	"Adult": [0.3, 0.4, 0.5, 0.6, 0.7],
	"Senior": [0.7, 0.8, 0.9, 1.0, 1.1]
}
```

Please note that the LBXGLT values are presented as floats and the values provided are just examples. The actual values may vary based on the dataset and the specific age groups considered for the "Adult" and "Senior" categories.