<PRE><B>Question 183387</B>
After selling tickets at school, Jeff had $6.00 in dime and quarters. If Jeff had 39 coins in total, how many of each coin did he have? 
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Quantity Equation: d  +  q  = 39
Value Equation...:10d + 25q = 600 cents
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Modify:
10d  + 10q  = 10*39
10d  + 25q  = 600
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Subtract 1st from 2nd to get:
15q = 600-390
q = 14 (# of quarters)
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Since d + q = 39, d + 14 = 39
So, d = 15 (# of dimes)
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Cheers,
Stan H.</PRE>