Discount retailer Dollar Tree (DLTR) won antitrust approval for its planned $9.2 billion buyout of Family Dollar (FDO) after it agreed to sell 330 of its rivals stores to private equity firm Sycamore Partners. The merger will create the country's largest dollar store chain, but the two retailers are quite different. Dollar General has a large assortment of items that sell for right around $1.00. Family Dollar sells items at well above $1.00, some are brand names. Dollar General operates by buying closeouts with its often changing merchandise, while at Family Dollar customers see higher prices and more stable supplies. Shares of Dollar Tree closed down 0.4% to $79.81 Thursday before the settlement announcement with the FTC.