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{\bf  Review of Percentages--ANSWERS}
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1.  14 gallons of paint  is what percentage of 43 gallons?  First: is it about 1\% or 10\% or 100\%? 
 14/43= 32.6 percent.   Approximation: 15/45 = 33 percent. 

2. 16 gallons is what percentage of 110 gallons?  First: is it about 1\% or 10\% or 100\%? 
  14.5 percent.  Approximation: 16/100 = 16 percent. 

3. What percentage of 45 gallons is  4 gallons?  First: is it about 1\% or 10\% or 100\%?  
   4/45 = 8.9 percent.   Approximation: 10 percent. 

4.  If we had 23 gallons at first, and then increased it by 55 gallons, what is the percentage increase? First: is it about 1\% or 10\% or 100\%? 
   55/23 = 239.1    Approximation: 200\%. The new amount would be 78 gallons. 

5. If  your weight increased by 19\% from 85 pounds,  how much did it increase? First: Did it increase by more 50 pounds?  
 85*.19 = 16.2 pounds.  About .2*80 = 16 pounds. 

6.  If   you weighed 63 pounds originally, and your weight increased by 3.32\%, how much would you weigh? First: More than 100 pounds, or less?  
  63 *1.0332 = 65.09 pounds.  About 60*.03 =  1.8 pound increase, so 63+1.8 = 64.8 pounds. 

7. What is your weight if you used to weigh 88 pounds, but then your weight rose 35\% over the next two years? First: More than 100 pounds?  
  88* 1.35 =  118.9 pounds.  About 90*.4 = 36 pound increase, so about 126 pounds. 

8. If 12.4 tons of coal is used, and that was 19\% of the  amount of coal  in the  coal pile, how much did the coal pile weigh? First: More than 20 tons?  
  12.4 = .19 X, so X = 12.4/.19 =  65.2 tons.   About 12/.2 = 12*5 = 60 tons. 

9. If 2.1 tons of steel is 88\% of the amount of steel the car company uses each hour, how much does it use each hour?  First: More than 10  tons?  
 2.1  = .88X, so X = 2.1/.88  = 2.39 tons.   About 1/2 = 2 tons. 

10. If 2.7\% of the usual daily tonnage of sulphuric acid was used today-- 180 tons-- what is the usual daily tonnage? First: More than 1,000 tons? 
  180 = .027X, so X = 180/.027 = 6,666.7 tons. About 200/.02 =200*50 = 10,000 tons. 

11. The catch of fish this week was 334\% of the catch last week, which was 4.3 tons. How much was caught this week?First: More than 8 tons?  \\
  X= 3.34 *4.3 so X = 3.34 * 4.3 = 14.4 tons. About 3*4 = 12 tons. 

12. If 2.2\% of men are convicted of burglary this year and that number is  234,333 men, what is the total population of men?  First: Is it more than 1 million? \\
 234,333 = .022*X,  X = 234333/0.22 = 10,651,500 men.    About 200 thousand/.02 = 200 thousand*50 = 10 million men. 

13. Mr. Jones's  corn yield  was 208 bushels per acre last year, but fell by 12.5\% this year. What is the yield this year?  First: More than 100 bushels per acre? \\
  It fell .125*208 = 26, so it fell to 182 bushels per acre.    A decline of about 200*.1= 20, so about 180 bushels per acre. 
 
14.  If 99.2\% of the chestnut trees were killed by the blight and 21 are left, how many were there originally? First: More than 100? \\
    That means 21 is .8% of the original number, so 21 = .008X and 21/.008 = X, so X = 2625. About 21/.01 = 2100. 

15.  If we had 23 gallons of paint  today, and then increased it by 55 gallons, what percentage of yesterday's amount of paint  is today's?    First: is it about 1\% or 10\% or 100\%?\\ Today we have 23+55 = 78, which 78/23 = 339% of yesterdays. About 75/25 gallons,which is 300%. 


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