34 A Handbook for Dairymen 



This problem may also be worked by simple pro- 

 portion : 



1 : 25 : : X : 500 



25x = 1 X 500 



25x = 500 



X = 20, number of pounds of 28 per cent 



cream there will be in the 500-pouiid mixture. 



— Answer. 



If there are 20 pounds of 28 per cent cream in the 

 500-pound mixture, the remainder will necessarily 

 be 3 per cent milk. 



Therefore, 500 — 20 ^ 480, number of pounds 

 of 3 per cent milk. — Answer. 



The number of pounds of 3 per cent milk can be 

 found directly by simple proportion: 



24 : 25 : : X : 500 



25x = 24 X 500 = 12,000 



X = 480, number of pounds of 3 per cent 



milk. — Answer. 



Proof. 



In working problems in standardization, it is al- 

 ways wise to prove the answer and check for mis- 

 takes. According to the conditions of the problem, 

 there would be 500 pounds of 4 per cent milk. This 

 amount of milk would contain 20 pounds of fat 

 (500 X .04 = 20). According to the results the 

 480 pounds of 3 per cent milk would contain 14.4 

 pounds of fat (480 X .03 = 14.4). The 20 pounds 

 of 28 per cent cream would contain 5.6 pounds of 

 fat (20 X .28 = 5:6). 



14.4 + 5.6 = 20 



Since the 500 pounds contain 20 pounds of fat 

 and the materials of which the 500 pounds is made 



