Oops, forgot to times by 100. My bad. That's 0.000014285571%.
But then we can remove over 7 billion people who have never made a basic mathematical error, as you're right - the ability to do arithmetic is a critical skill in extreme mountaineering.
This leaves us with a world population of 1. It must feel great to be the only inerrant mathematical mountaineer in the world - was that skill learned, or is it innate?
