NOTATION AND NUMERATION. 229 



Per cent means by the hundred. For instance : 5 

 per cent of a number means 5 hi.indreths; that is, 

 5/100 or .05 of that number ; 5 per cent of 240 is 

 240X5/100, or (240X5)-^100=12; 25 percent of 

 850 is 850X25/100, or (850X25)-f-100=213.5. 



When we say that the overrun of a certain cream- 

 ery is twenty per cent, we mean that for every 100 

 pounds of butter fat received, there was made 120 

 pounds of butter. If the creamery had received 800 

 pounds of butter fat and obtained an overrun of 20 

 per cent, the total butter made would be 800X20-H 

 100=160+800=960 pounds of butter. 



Solution: 800X20=16,000; 16,000-^100=160 lbs. 

 overrun; 800+160=960 lbs. of butter made. 



The sign per cent is % and is read per cent. 

 Thus, 8% is read eight per cent, 151/3% is read fif- 

 teen and one-half per cent, etc. 



When expressing the per cent of a number to be 

 used in calculations, it is necessary to express it 

 decimally instead of fractionally. Thus, instead of 

 expressing 5%, 20%, 30%, as 5/100, 20/100, 30/100, 

 express them as .05, .20, .30, etc. 



The following table will show how per cent can 

 be expressed : 



14. Table No. III. Different ways of expressing 

 per cent. 



Per cent. Decimal. Fraction. 



1 



1% .01 



100 



5 

 5% .05 — ■ 



100 



