Accuracy issue (presumably) with low numbers

[willow-mouse]

My colleague has an issue with summing a list. I've shown the original below, and the permutations I've tried to the right which all result in the correct zero sum.

Any idea how this happens?

Cell	Original	A>Z	Z>A	Swapped
A1	22.05	-427.85	661	22.05
A2	-7.05	-232	22.05	-7.05
A3	661	-20.75	6.2	661
A4	-232	-7.05	-1.6	-232
A5	-20.75	-1.6	-7.05	-20.75
A6	6.2	6.2	-20.75	6.2
A7	-427.85	22.05	-232	-1.6
A8	-1.6	661	-427.85	-427.85
Sum(A1:A8)	-3.42E-14	0.00	0.00	0.00

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[Fluff]

Duplicate https://www.mrexcel.com/forum/excel...issue-presumably-low-numbers.html#post5200521

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