Math News: Numbers Games
I went on a date today for Valentine’s Day, and I remember thinking, hey I’ll write something today about dating and that’ll be a welcome change from writing about politics yesterday. But I’m damned if I remember what mathematical thing I might have had to say about dating this morning. All the synapses were firing this morning after two cups of coffee, but yeah, I can’t really think of anything to say about it now.
Of course, one of the Math lessons that I was exposed to as a high school teacher going to summer math conferences was a lesson about the “one half plus seven” rule, which is I guess a fun dating-related math thing, so yeah, okay I’ll talk about that.
The one-half-plus seven rule is a mathematical guide to how young of a person you ought to be able to allow yourself to date. It is a fairly useless rule to twentysomethings, who really only want to date each other anyway and aren’t constrained by this rule. But then it turns out that men of all age brackets want to date women in their twenties. The half-plus seven rule tells men when this is socially acceptable.
It’s not binding. It’s just a helpful guide. I’ve heard second-hand (actually I heard the Edie Falco character complaining about it on Louis CK’s Horace and Pete) that it is somewhat nauseating to women when men date way-younger women. Seeing as men are going to want to date way younger women anyway, it helps to have a formula to go by that attempts to guess when this nausea might be activated.
So at age 40, a man can date a woman who is 27. Half of 40 is 20, plus seven is 27. Now in the math lesson as it was taught to me at that conference, this didn’t apply only to men. A 40-year-old woman would be similarly bound to date men who were 27 and above. But practically speaking, this rule is a guide for men.
Anyway! The rule is based on a linear equation. You can go to desmos.com and type y=0.5x + 7 into the graphing calculator, and a line will appear — tracing a diagonal path across the page. If you count how many squares up it goes versus how many squares over it goes, where the man’s age is on the x-axis and the allowable woman’s age is on the y-axis … well, every time you go over 10 years on the x-axis, you go up 5 years on the y-axis. So when he turns 50, the man can date a 32-year-old. At 60, he can date a 37-year-old. Forget about the man and the woman, for a minute, and try to notice the regularity in the way the numbers rise up. It’s a straight line.
That’s the major payoff of the lesson. It’s fun to teach it; all the students gawk and cringe and laugh and joke about it, and hey! You’ve tricked them into taking interest in a linear equation. Of course, at that point in my teaching career, I didn’t really even know how to do that, how to enjoy a win. I’d simply press forward into the second “challenge” portion of the lesson, which has to do with how the same rule can be used to state how much older one should be allowed to date as well.
I was thinking, I guess I’ll admit, about creating a whole dating reality show around my own life. That would be my fun way about telling some weird stories that I haven’t figured out if and whether I can tell at all. Maybe that was what I meant to write about. Although I’m not sure what it has to do with numbers.