How to sales are calculated in supermarket

i want to start a new supermarket business in my area  in my project report  for a period of purchase of stock only  is  RS1000000 if iam adding 25% on it is getting 1250000 sales it is getting loss because purchase is 1000000 and yearlymy operating expenses are exluding purchase of stock is 1716208 like manager salary,worker salary administration  and depreciation etc now how i should calculate my sales to get profit i have only this doubt sir please give me a answer to this  sir