Francis owns a cake shop. She is currently preparing cupcakes (x) and cookies (y) for two birthday parties. The first birthday party ordered 20 cupcakes and 40 cookies and their total cost was $61. The second birthday party ordered 30 cupcakes and 30 cookies. Their total cost was $64.50.

Anut store normally sells cashews for? $4.00 per pound and peanuts for? $1.50 per pound. but at the end of the month the peanuts had not sold? well, so, in order to sell 40 pounds of? peanuts, the manager decided to mix the 40 pounds of peanuts with some cashews and sell the mixture for $2.00 per pound. how many pounds of cashews should be mixed with the peanuts to ensure no change in the? profit?