Question 146391: The Good Seed Flower Shop sells its own brand of fertilizer. It mixes one brand of fertilizer that contains 7% nitrogen with another than contains 8% nitrogen. The resulting mixture contains 7.7% nitrogen. How many pounds of the 7% fertilizer must be used to make 400 pounds of the 7.7% mixture? Answer by checkley77(12569) (Show Source):
You can put this solution on YOUR website! .07x+.08(400-x)=.077*400
x=120 pds. of 7% nitrogen is used.
400-120=380 pds. of 8% is used.