Avarage of remaning balance needed by formula pls

[marko737]

hello all,

i need a formula to help me getting the remaning avarage of the below

Buy 100 X 1500 = 150000 i need here avrg of the buying 100
buy 152 X 1505 = 228760 i need here the avrg of buying 252
sell 200 X 1510 = 302000 i need here the profit of the selling according to the avarage
also i need the remaning balance of buy after the sell and its avarage of remaining

also pls tell me how how to attach a excell file on this form to make things easier and give you examples over excell file