my brain isn't working, i have an exam tomorrow i just can't do ****. Thanks.
The overall price is made up of 2 parts. A fixed price and a variable price. The fixed price is constant for all unit sizes. So if we call the fixed price x and express the variable price in terms of the total price and fixed price (Price-x=variable). If we assume the variable price is linearly related to the size, 3000*n+x=41000 and 11000*n+x=105000. Do you think you can go from there?