PERCENTAGE 



4581 



PERCENTAGE 



Practical Problems. (1) A 20-acre field 

 yielded 480 bushels of corn one year; the fol- 

 lowing year its product was increased 7%%. 

 What was the value of the increase, com selling 

 at $1 per bushel? 



First crop =2 4 bu. 



Number bu. increase = . 07% X 480 = 35.40 



Value of increase^ 35. 40x$l = $35. 40 



(2) Sugar sold at 6% cents per pound; it 

 rose in price 507r. For what did it sell then? 



First selling: price = 



Increase 50 X 6 %<f = 



Second selling price = 6%<+3 V 4 t = 



(3) Living expenses rose 35% from January 

 to July. What salary should a man receive 

 in July, who in January was getting $24 a week, 

 so that the increase in salary will correspond 

 to the increase in expenses? 



(4) A school district receives $788.50 one year 

 for expenses. The state pays 28% of it, the 

 county 32% of it, and the district the rest of 

 it. How much does each pay? 



Whole tax = $788. 50 



State tax = .28 X $788.50 = $220.78 



County tax = .32X$788.50 = $252. 32 



District tax=(1.00-.60)X$788.50 = $315.40 



(5) If wheat selling at $1.90 falls 10%, for 

 what does it sell? 



(6) A record jump was 12 feet 9 inches. 

 An athlete breaks the record by an increase 

 of 2%. What is his jump? Answer, 13 feet 

 .06 inches. 



First record = 1 2 ft. 9 in. 



Increase = . 02 X (12 ft. 9 in.) =.24 ft. + .18 in. 



New record = 12.2 4 ft. + 9. 18 in. 



.24 ft. = . 24X12 in. = 2.88 in. 



New record = 12 ft. + 2. 88 in. + 9.18 in. = 13 ft.+ 

 .06 in. 



Finding What Per Cent One Number Is of 

 Another. Note the following: 



$- Is what part of $8? 



$4 in what part of $8? 



$3 In what part of $8? 



$6 in what part of $8? 



$7 la what part of $8? 



Vi 



Express the above answers in hundn.lth 



Express with the symbol % : 



$2 is 26% of $8 



$4 I. 60% of $8 



fS l 87H% of $8 



$6 la 76% of $8 



$7 is 87H% Of $8 



Common fractions may be expressed with the 

 per cent sign : 



fc=20%, fc = 40%, % = 60%. 16=80%. % = 



1*4%. 



(Refer to DECIMAL FRACTIONS for reduction 

 of common fractions to decimal fractions.) 



Any fractional part can be expressed as 

 hundredths and therefore as per cent, as shown 

 below: 



135 trees in an orchard of 180 trees are cherry 

 trees, 18 are plum trees and the rest are peach 

 trees. What per cent of the orchard is cherry 

 trees? Plum trees? Peach trees? 



Number trees = 180 

 Part cherry = ii80=tt = 76% 

 Part plum =i^8o = Vio=10% 

 Part peach =2viso=%o=15% 



This follows very simply from work in com- 

 mon fractions; we find what part one number 

 is of another and express that part in hun- 

 dredths or per cent. 



Practical Problems. (1) A gardener plant- 

 ing 40 acres of land put 7 acres into sweet com, 

 15 acres into potatoes, 13 acres into tomatoes 

 and 5 acres into lettuce, radishes, etc. What 

 per cent of his land is given to com? Pota- 

 toes? Tomatoes? Lettuce? 



Part to corn = 7/40=^ = 



Part to potatoes = i%o= = 



Part to tomatoes = i% =- 

 Part to 



= 32 V4% 



(2) A man receives a salary of $135 a month. 

 He pays per month $25 for rent, $36 for food, 

 $15 for clothes. What per cent of his salary 

 does he pay for each? 



Part for rent=29i M = 



Part for food = 39i== 



Part for clothes = %s= = 



(3) 2800 pounds of milk from one dairy gave 



84 pounds of butter fat; 2400 pounds from 



her dairy gave 84 pounds of fat. What 



per cent butter fat did the milk from 



dairy give? 



Number Ib. of milk = 2800 

 Number Ib. of fat = 84 

 Part fnt = 14voo = : hoo = 2% 

 Number Ib. of milk = 2400 

 Number Ib. of fat = 84 

 Part fat 



(4) 4 inches is what per cent of 1 foot? 



