How make a expensive thing in our target price? example: Item no. A 1st grade quality in 200$/kg. and item no. B is 4th grade quality in 50$/kg. so, how much ratio mix, item no. B in Item no. A to make in target price 150$/kg. Kindly advise explanation with detail enable to do my self calculate at my place. Thanks 150 is 3/4 of 200 so the ratio is 3/4