A commoditys spot price is $60 and a 5 months long September futures price is $58. Consider a company that entered into the 5 months long September futures contracts to hedge its purchase of the commodity 3 months later. Then after 3 months, when the spot price is $63 and the September futures price is $64, the company closed out its futures position and bought the asset in the spot market. Assuming interest rates are zero, what is the effective price (after taking account of hedging) paid by the company? The correct answer is 57. Can you show the formulae and calculations how to achieve the answer?