AMC 10 Weekly Practice Round 2

A store purchased a batch of goods and planned to sell them at a markup. After selling of the goods at the marked-up price, the store decided to sell the remaining goods at off in order to clear the stock quickly. After all the goods were sold, the store was unexpectedly charged an additional dollars tax, which caused the actual profit to be only half of the originally expected profit. What was the cost price of this batch of goods?