Here is what I have done.
I have created one new blank InfoPath Form and added (for example) 3 fields, say A1, B1, C1.
A1 = Decimal Field = Decimal Preceding : Auto
B1 = Decimal Field = Decimal Preceding : Auto
C1 = Decimal Field (Calculation C1 = A1 * B1) = Decimal Preceding : 2
Now, when I preview InfoPath forms and enter values like
A1 = 5.29
B1 = 4.23
I gets C1 = 22.38
Works fine.
I deployed it to the SharePoint Library, configured Submit Options to save data to the same library.
Now, in my library, I said Add New Item (Add Document) which opens up the InfoPath form and I entered values as below:
A1 = 5.29
B1 = 4.23
I gets C1 = 22.38
Works fine.
BUT..now when I click on submit data, in my library, in C1 column, I get 22.3767
That's the problem (why not 2 decimal only, why 4?)
This was just an example, as per my calculation, the real value is 15.67 but in my library, I'm getting it as 15.6666666666
Any solution?