MS-Excel 2003

From last two months I am making comparative reports related to costing of material in MS-Excel. I have used many mathematical formulas and found that it possible to display a cell value with or without decimal value even if cell contains the result of some formula but if you use the value of this formula as a whole (without decimal value) in calculation with some other cell the result will be calculated taking in consideration decimal values also. Let me shown you an example

Cell A1 = 1012 * 0.6 (with decimal value the result will be 607.20)
Cell B1 = 15
Cell C1 = A1 * B1 = 9108

Use of 2 decimal point
The value of C1 is 9108 when you use 2 decimal points
Without 2 decimal point
The value of C1 is 9108 when you use 2 decimal points

In both the cases the result is same.

While in actual calculation if we calculate 607.2 * 15 = 9108 and 607* 15 = 9105.

I think it is a loophole in MS-Excel if anyone out of you knows the solution, please mention.