Top Definition

Guys have mathematical rules on the ages of socially acceptable sexual partners (half your age plus seven is a good one).

To do fuck maths is to mathematically work out whether somebody falls within the age limits.

To do fuck maths is to mathematically work out whether somebody falls within the age limits.

I'm 20 she's 16, which is not quite half my age plus seven. But I did the fuck maths and in 2 years I'll be 22 she'll be 18 which will make it OK.

by The Dangerous One
July 20, 2005