FARM AND SCHOOL PROBLEMS. 



means $% nitrogen, $% phosphorus, 10% potash. Thus a for- 

 mula always indicates that the elements are given in the follow- 

 ing order : 



AVERAGE COMPOSITION OF FERTILIZERS. 



PROBLEMS. 



1. If a 50 bushel crop of corn takes from the soil 75 pounds of 

 nitrogen, 12 pounds of phosphorus, and 36 pounds of potassium, how 

 many pounds of a 2-8-2 fertilizer would be required to supply the potas- 



