Yeah. The 7.5 times (or is it 9.5 times, I forget) thing that has been thrown around since the cold war days never rings true to me.

The primary and secondary strikes for both sides will take out people living close to either a military installation or a major city.

Also there's no way even a world war would involve every single country and every single island. There's no way human life would be entirely obliterated. Most us posting here, perhaps. Certainly I'd likely be taken out in the second or third wave (close to London and also close to a military base). But life would go on.