you want to apply a discount for the product

in your table you said you had for each product a discount amout

Assuming this is the reference table 1

A1 Product_1

B1 Retail price £100

C1 Discount 15%

Then in your other sheet

as an example

A2 Quantity = 5

B2 Dropdown box for product = product_1

C2 vlookup for retail price = Vlookup(B2, RangeOfTable, 2, false) returns £100

D2 Calculate extended price (A2*C2) = 100 * 5 = 500

now we need to discount by 15%

which means the price is 85% of the total 100-15

SO E2 would need to lookup the % value

=Vlookup(B2, RangeOfTable, 3, false)

returns 15 or 0.15 (as its a %)

then 1-Vlookup(B2, RangeOfTable, 3, false)

=85% or 0.85

* by the total price

D2* (1-Vlookup(B2, RangeOfTable, 3, false))

= 500*0.85

= £425

does that explain it - and is that what you required