Question 371197
On a table there are 30 coins. Some are quarters and some are dimes. Their value is $4.05. How many of each coin are there?

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let there be x quarters
dimes will be balance = 30-x
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Value = $4.05 = 405 cents
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25x+10(30-x)=405
25x+300-10x=405
15x=405-300
15x=105
/15
15x/15 = 105/15
x=7 quarters
dimes = 23 
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m.ananth@hotmail.ca