74 Gardening 
(3) A pound of potassium sulfate is 54 per cent potash. How 
many pounds of potassium sulfate are needed to supply the potash 
required ? ; 
(4) Add the three amounts (or the amounts nearest the next 
even number for any that are not even). If the totalis less than 
1oo pounds, the difference indicates the amount of dry sand or 
earth that is to be included in the mixture. 
D. Is it possible to make a mixture of sodium nitrate, acid 
phosphate, and potassium sulfate that will contain 8 per cent 
nitrogen, ro per cent phosphoric acid, and 15 per cent potash? 
(Work out this problem, basing your calculation on the facts 
learned in the previous problems. Determine the amount neces- 
sary for each ingredient.) 
