my package is rounding up excel Item values

Hi Gurus,

I have a package that calculates qty with Item No's.For ex:

ITem No Qty  Result

1          2          2
1.1       3         6(2*3)
1.2        4          8(2*4)
1.3        1         2 (2*1)
1.4        1         2(2*1)
1.5       2         2(2*1)this is qty from parent 2-which is wrong.It should multiply by ItemNo 1 parent Qty-2)
1.6       2          2
1.7       3         3
1.8       4         4
2         1          1
2.1      2          2
2.2      3         3
2.3     4         4

If you obsereve for Result col:

we have two parent Item No which are 1,2. For ItemNo 1 childs(1.1-1.8) we have to multiply by ItemNo 1 QTY which is 2. 
My SSIS package is calculating fine for numbers from (1.1-1.4) but if any item no is greater than 4 (ie. 1.5-1.9).It is rounding up and multiplying with ITem No 2 qty. But I want that to multply with Item No 1 Qty.

Please help me with this. Let me knoe if it is not clear.

2.2      3         3
2.3     4         4