Polyhidron Corporation produces 5-gallon plastic buckets. The company expects to produce 430,000 buckets in 2018. Polyhidron purchases high-quality plastic granules for the production of buckets. Each pound of plastic granules produces two 5-gallon buckets. Target ending inventory of the company is 35,200 pounds of plastic granules; its beginning inventory is 22,500. Compute how many pounds of plastic granules need to be purchased in 2018.