Question 808921:  Paula has 30 coins in dimes and quarters. Their total value is $4.50. How many coins of each type does she have?  
 
 Answer by TimothyLamb(4379)      (Show Source): 
You can  put this solution on YOUR website! d + q = 30 
q = 30 - d 
10d + 25q = 450 
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10d + 25(30 - d) = 450 
10d + 750 - 25d = 450 
15d = 300 
Answer: 
d = 20 
q = 10 
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