I have always said to is impossible to accurately judge the ages of 'unfortunates'. Their hard life makes them look older [ the 15 year old looks as if she is in her twenties ] but some older women if they take care of themselves can look younger so the ages at both ends merge. I don't believe any man can accurately guess the age of a woman, so I think those who believe the age of the ripper victims was a factor are barking up the wrong tree.It was the availability and vulnerability of the victims that was the factor particularly of alcohol is involved. Mary Kelly was marked out because she had a room of her own. In the past she had been a notorious prostitute hanging out at the local pubs, The Ten Bells and The Brittania, but had been off the streets for a year or so, but within a few days of Joe leaving, she was back touting for business, an opportunity not to be missed.