I saw this and thought it quite a good little puzzle (click image for full sized image), so thought I'd post it here to stimulate the minds of my readers.
![Puzzle from Popular Science April 1960](https://photos32.flickr.com/38878921_017cc066ed_m.jpg)
So then, what number flat do they live in and what are the 3 ages? Oh, and use a bit of reasonable thinking too.