This mischievous courtship feint is kind of nerdy, but it really works in the SWPLopolises where girls tend to be a little smarter, or at least more concerned about signaling their smarts to demanding alpha males.
When a girl asks how old you are (because you regularly hit on conspicuously younger women), say
“The square root of [X].”
So, if you’re 35, you’d say, “The square root of 1,200.” Tell her to “round up” because “all women prefer an established older man”. Bust her chops and say you’ll add points to her score if she doesn’t use her phone calculator.
Most girls will play along, especially if you frame your challenge less as an earnest invitation to turbocharge a conversation and more as an aloof swipe at her insolence for asking such lame questions.
She’ll guess (usually younger, b/c girls will form-fit you into a suitable male mold if you sufficiently intrigue them), and, as per the usual CH advice, your reply should be something along the lines of “wow, you’re really good at this!” or “well done!”, implying that she nailed your age without ever actually confirming her guess as true or not.
PS: If you look like a spitting image of a math olympiad winner, you might want to field test this baby on a few uninspiring ladies first, and gauge their reactions. I’m thinking that very nerdy-looking men would be mistaken by girls as the type of men who would seriously consider a math question to be appropriate flirting, which would cause the tactic to backfire. Alternately, if the nerdy-looking man projects a flippant self-awareness while delivering the line, women could become interested by the contrast between the outer nerd and his inner ZFG confidence.
PPS There is always an ulterior, goal-directed undercurrent buoying Game techniques. In this instance, the conversation is framed as a challenge to the woman, which psychologically provokes a feeling in her that she has something to prove, which coaxes her into a “chaser” role and alters her perception of the man as having higher mate value than he otherwise would have had he dutifully submitted to the rules of her interrogation.