Translation:Do you understand the metric system?
Gen-X in the UK probably work in a mixture of metric and Imperial; Boomers and older generally struggle with metric. It's only really Millennials who are likely to really understand metric here — and even then some things we all just know in Imperial, people's heights for example.
Well I'm a boomer and apart from cooking weights and for some reason my own height, I can't think in imperial at all now!
Don't forget the US! I learned the metric system in the '70s, but since we don't use it, I don't think in it. I have to stop and think to convert.
I always take the metric system for granted, but I know that you need to be very lucky if you want to discuss average car consumption in liters/kilometer in the UK....:-) And I always struggle with the miles per gallon concept......... :-)