You operate a swimming pool installation company. You sell three different size pools and can attach a whirlpool, waterfall, or fountain for an extra charge. Recently you sold 12 small pools, 8 medium pools and 9 large pools at a cost of $7,500, $11,000, and $18,000 respectively. In addition, you sold 5 whirlpools at a price of $5,250, 8 waterfalls at a price of $4,000, and 4 fountains at a price of $4,800. Your total revenue was $x.