How to get an accurate value by dividing decimals

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I have this code

C#

decimal total = 2m;
decimal discount = 0.2m;
decimal disPercent = discount / total;

disPercent value should be 0.0909090909090909
but I get 0.1
what should I do to get 0.0909090909090909?

note that the values are for example, I always get them from database as decimal values

What I have tried:

C#

decimal total = 2m;
decimal discount = 0.2m;
decimal disPercent = decimal.Divide(discount, total);

not working

Posted 26-Nov-16 0:39am

M. Daban

Updated 26-Nov-16 0:51am

v2

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3 solutions

Solution 2

0.2 / 2 does, in fact, equal 0.1. I am thinking that your question may have needed to include the 0.2 in the total, so 2.0 is paid, 0.2 is discount, and 2.2 is total. Then if you divide 0.2 by 2.2, you will get your expected result of 0.0909 recurring (effectively 1/11).

Posted 26-Nov-16 0:46am

Midi_Mick

Updated 26-Nov-16 0:47am

v2

Solution 3

Dividing decimals already returns an accurate value (more accurate than doing ANY math with floating point values).

Posted 26-Nov-16 0:51am

#realJSOP

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OriginalGriff · Accepted Answer · 2016-11-26T00:46:00

Solution 1

Why do you think that 0.2 / 2.0 is 0.0909090909...
The maths I was taught as a child says different:

0.2 / 2.0 == 2.0 / 20.0 == 1.0 / 10.0 == 0.1

Posted 26-Nov-16 0:46am

OriginalGriff

Comments

M. Daban 26-Nov-16 7:01am

ohmy bad, sorry I did all my calculations on 2.2/0.2 not 2/0.2
it's alzheimer :(

OriginalGriff 26-Nov-16 7:12am

I know the feeling well! :laugh: