Based on prior knowledge, there is a general understanding that body mass index (BMI) tends to increase with age due to factors such as a slower metabolism and decreased physical activity. Therefore, it is expected that higher values of BMI are more likely to be associated with the "Senior" age group, while lower values of BMI are more likely to be associated with the "Adult" age group.

Here is a dictionary containing 5 typical BMXBMI values for each target class:

```json
{
	"Adult": [22.5, 23.8, 25.1, 26.4, 28.9],
	"Senior": [26.7, 29.3, 31.2, 33.8, 35.6]
}
```

Please note that these values are just examples and may not reflect the actual relationship between BMXBMI and age groups in the given dataset.