Not understanding MROUND
 

Can somone answer an MROUND question for me?

Situation:

MROUND with a multiple of .1 rounds 773.65 to 773.6
MROUND with a multiple of .1 rounds 921.65 to 921.7

Isn't the remainder the same for both values? Shouldn't it round up
for both of these values?

Not understanding MROUND
 

You have hit one problems associated with the way computers (not just Excel)
stores numbers. A decimal number like 773.65 must be convert to a binary
number. Sometimes an exact conversion is not possible. See these sites for
more detail
Visual Basic and Arithmetic Precision
http://support.microsoft.com/default...NoWebContent=1
Tutorial to Understand IEEE Floating-Point Errors
http://support.microsoft.com/default...NoWebContent=1
What Every Computer Scientist Should Know About Floating Point
http://docs.sun.com/source/806-3568/ncg_goldberg.html
Go to source
http://www.cpearson.com/excel/rounding.htm

If you type 773.65 in A1 and in B1 use =MROUND(A1,0.1) you get 773.6 (an
erroneous result)
But if in A2 you use =A1+0.0000000000001 then =MROUND(A2,0.1) gives the
correct value of 773.7. Adding that small amount overcame the binary
conversion problem. As you are interested in only once decimal place you
might consider using =MROUND(A1+0.0001, 0.1)

Note when I use correct/incorrect I assume we are not using the
'round-to-even' convention.

best wishes
--
Bernard V Liengme
Microsoft Excel MVP
www.stfx.ca/people/bliengme
remove caps from email

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Can somone answer an MROUND question for me?

Situation:

MROUND with a multiple of .1 rounds 773.65 to 773.6
MROUND with a multiple of .1 rounds 921.65 to 921.7

Isn't the remainder the same for both values? Shouldn't it round up
for both of these values?