Then it wouldn’t be reasonable to assume the US would collapse right at the average (mean) though. If the majority of empires collapsed at the same age (the mode) it would be different, but the mean tells you very little about when any particular empire will collapse.
The mean number of children per household is a decimal, that doesn’t mean any households have partial children.
You do know what average means in this context, right? You divide the sum of the empires’ years by the number of empires.
Then it wouldn’t be reasonable to assume the US would collapse right at the average (mean) though. If the majority of empires collapsed at the same age (the mode) it would be different, but the mean tells you very little about when any particular empire will collapse.
The mean number of children per household is a decimal, that doesn’t mean any households have partial children.