Export datatable to excel (missing decimal values)

hello experts

i m exporting dataset to excel through light weight process. (using xml and html)  I have created columns in datatable like this

dt.columns.add(new datacolum("clmname1"))

dt.columns.add(new datacolum("clmname2"))

when exporting everyrow is exported to excel but the row containg value "3.90" is exported as "3.9"  the decimal 0 is missing  in excel .

urgent 

how will id do that........?

 

thanks in advance..........

 
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