assigning same percentage discount to four different columns with different prices

Thank you Nikolino. I copied and pasted to a new work book the part where the issue I asked for help is. I cannot send you the original file which I have saved it on three different drivers for safety.
The original file contains proprietary info. The formulas are all  discombobulated because some of the referenced cells are not present on this sample. In this sample you'll see the description of the product (column A), columns H through M are four columns where different configuration prices are for the listed products. Columns Q through AO, are the discounts I wanted to apply to the products based on quantity. As you can see I had to created 6 columns (10% through 30%) for each different product configuration so I have 26 columns. Although it is not difficult to cut and paste the formulas, I had to go through each cell to make sure the proper referenced cells were correct and to make the necessary adjustments . Spent too much time doing this and was looking for a simpler process. This is an estimating spreadsheet for a small print shop.

I will place the file on the original post.

Thank you.