Fertilizer is sold in bags labelled with the amount of nitrogen ( n), phosphoric acid ( p2os), and potash k20) present. the mixture of these nutrients varies from one type of fertilizer to the next. for example, a bag of vigoro ultra turf fertilizer contains 29 pounds of nitrogen, 3 pounds of phosphoric acid, and 4 pounds of potash. another type of fertilizer, parker's premium starter, has 18 pounds of nitrogen, 25 pounds of phosphoric acid, and 6 pounds of potash per bag. determine the number of bags of each type required to yield a mixture containing 76 pounds of nitrogen, 31 pounds of phosphoric acid, and 14 pounds of potash. the mixture contains bags of vigoro, and bags of parker's.