This is just the usual numerical 'error' due to the limitations of floating point arithmetic.
ans = 2.5202e-14
It's not zero, but it's still pretty small, considering that 100,000 numbers are involved. If you try format hex, which shows what's taking place in memory,
ans = 3fb999999999999a
it doesn't take an expert in floating point to see that there is some compromise rounding going on. Most numbers with decimal digits are like this. On the other hand,
ans = 0000000000000000
and you get zero, because .125 = 1/8 has an exact binary representation:
ans = 3fc0000000000000