That'd probably be from the center of each district, so it's a decent average estimate. No telling exactly where in Yūrakuchō and Shinbashi each party is, though.
unicode said: Google map says 1.5km, or 6 minutes of driving.
That's not counting the heavy traffic that must be going on.
Bi-bi-The end of opening day.We're Almost ThereWe'll take a taxi to the restaurant to close our day.Girls are waitingLet's split up into two cabs.I'm so hungry...YūrakuchōWe can't ride with 5 people.Kogasa and Yamame are late...Ain't this Shinbashi?!I'm sorry! I'm really sorry!Yamame-san, calm down!!Umm...Let's try calling them.How 'bout I infect you with somethin'!!Dang it, driver! I said Yūrakuchō, didn't I?!