N/2+7

I'm in a meeting at work this morning when suddenly my boss makes a comment about a well respected guy who works for another bank, and who we all know.

"Actually, that guy hasn't been very productive since he got married to that young woman a few years ago!"

We all laugh, because my boss is clearly implying that instead of making money for the bank that he works for, he's got better things to do!

"But he broke the rule," my boss continues, "because she was only 25 years old when he must have been about 52."

"What rule are you talking about?" I ask.

"N/2+7," replies my boss cryptically, "where N is the age of the man. No man should marry a woman who's younger than N/2+7. So this guy's limit should have been a woman aged 33!"

"But who says?" asks another colleague, "I've never heard that before!"

"It's just a reliable rule of thumb," says my boss confidently, "something's just bound to go wrong if you break the rule. Hasn't anyone else heard of that before?"

We all shake our heads and soon the meeting moves on to work related matters. But for the last few minutes of the meeting I'm thinking about the rule that my boss mentioned.

It even seems sensible for young guys. If a guy is 18, the rule would say that his female partner shouldn't be younger than 16, which works in the UK at least because that's the age of consent. The rule was stated for heterosexual guys and marriage of course, but even so, I can't help wondering. Perhaps it's also a sensible rule for gay guys?