Simple formula doesn't add up right

[ChrisHar]

I've been seeing some weird results with some simple adding/subtracting formulas, for example

A1 is 1.1
A2 is 0.8
A3 is 0.3
A4 is 0
A5 is =A1-A2-A3-A4

A5 displays 55.55112E-17 when formatted General, and 0.00000000000000005551115123 when formatted to Number, which is essentially the same thing.

Why doesn't it display zero?

 

[Aladin Akyurek]

That's due to the vagaries of binary represention computers use.

Try:

=ROUND(A1-A2-A3-A4<strike></strike>,0)

 

[Joe4]

I would think that because most of the terms in A1:A4 have one decimal place, they would probably want to round to one decimal instead of the nearest whole number, i.e.
=ROUND(A1-A2-A3-A4<strike style="color: rgb(51, 51, 51); background-color: rgb(250, 250, 250);"></strike>,1)

Here is an explanation of the issue that Aladin is referring to:
https://support.microsoft.com/en-us...ithmetic-may-give-inaccurate-results-in-excel

By the way, welcome to the board!

 

[ChrisHar]

Thanks Aladin and Joe, i figured there would be a logical explanation for it! Nice article explaining it too.