CHAPTER IX. 
CREAMERY CALCULATION. 
Find the Average Per Cent of Fat.—In calculating the 
average per cent of fat from a number of cows, or the milk 
furnished by the different patrons, the mistake of adding the 
tests of all the samples together and dividing the sum by the 
total number of samples tested is often made. Milk from 
different patrons, or from different cows, will always vary, 
some in quality and some in quantity, and in order to get a 
correct average test, both quantity and quality must be taken 
into consideration. The wrong way of calculating the average 
percentage may be illustrated as follows: 
Sample. Milk Delivered. Per cent Fat. 
1 50 Ibs. 5.0 
2 100 ‘‘ 4.5 
3 500 <‘‘ 3.0 
4 300 ‘‘ 3.5 
4)16% 
4 
The average test, according to the wrong method, =4%. 
The correct way of calculating the average percentage may 
be illustrated as follows: 
Sample. Milk Delivered. Per cent Fat. 
1 50 Ibs. 5.0= 2.5 Ibs. fat 
2 100 ‘‘ 4.56= 4.5  « 
3 500 ‘‘ 3.0=15.0 ‘* <«§ 
4 300 ‘‘ 8.5=10.5 “ ¢F 
950 Ibs. 950)32.5 Ibs. fat 
3.42 
105 
