General Discussion

Imagine you have a pile of 2 million pennies to count and divide the labor to 1000 people each of whom count 2000 pennies. Now, there almost certainly will be some error involved in the process. Each person might well make an error of 1 percent, on average, but the total error is very unlikely to be even half of a percent. Why is that? Because the errors are equally likely to be in either direction and some of the errors will therefore cancel out each other. So even if each person had 1% error the total error may well be 0.25% or less. The machine counts are even more accurate that this example so the total error will be even less.