Conclusion: Your computer is haunted.
I'm assuming either he stopped at the wrong place in the debugging or copy/paste error.
Overall These all appear as expected.
Dividing by 0.1 is the same as multiplying by ten.
I'm assuming you mistyped or selected the x value after the first division because the before and after values didn't change.
The values are REALLY small, which is concerning.
The forces are:
-0.000026226
-0.00000000061118
0.0000256299
When you start working with bigger numbers, very often the CPU needs to bring them to the same scale.
We'll use addition because it is easy.
So let's say we're adding that acceleration to an existing acceleration:
10.1234 + -0.00000000061118
The result is a destructive operation. The first thing the CPU needs to do is bring them up to the same scale, and it has roughly six decimal digits of precision. So it rounds to (10.1234) + (-0.00000) = (10.1234)
Which probably leads to a result different from what he wanted, but correct (within precision requirements) for floating point math.