Arch: division including a float to obtain correct result

[vocx-fc]

The LGTM code analyzer detects an issue which just affects Python 2.

In Python 3 this division will produce the correct floating point value.

Forum discussion: Arch Fence

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[furti]

Thanks for the fix.

The question is if it wouldn't be better to add "from future import division" to the top of the file.

There are more Divisions in the code that might produce wrong results.

[vocx-fc]

This is a simpler fix.