Strange Strangers on a Train

"Excuse me, mate, do you know the speed of light?"

Not a question I'd exactly anticipated, but since I'd been listening in on their conversation (which had bounced backwards and forwards between English and German), I was somewhat prepared.

Two nerds, arguing over the speed of light, on a train. At one point, they'd involved several hapless Japanese tourists in their debate, and at another, they were pointing out to two girls that this wasn't the best way for them to pick people up on trains, and that they did do better chat-up lines. As they headed towards the door, they asked a few people, me being the last of them, if they knew which of them was closer.

Given options of 3*10^8 (or "dreimal zehn hoch acht" as he'd been stating his case) and 1.1*10^9, I helped Guy No. 1 to victory.

It was only after they got off the train that I realised they were both right - one's in m/s and the other's in km/hr.

Oops.