SOLUTION: Merlin has 20 coins in quarters and dimes. The total value of the coins is $3.95. How many coins of each kind does he have?

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Question 61587: Merlin has 20 coins in quarters and dimes. The total value of the coins is $3.95. How many coins of each kind does he have?
Found 2 solutions by stanbon, joyofmath:
Answer by stanbon(75887) About Me  (Show Source):
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Merlin has 20 coins in quarters and dimes. The total value of the coins is $3.95. How many coins of each kind does he have?
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Let number of dimes be "x"; value of these is 10x cents
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The number of quarters is "20-x" ; value of these is 25(20-x)=500-25x cents
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EQUATION:
value + value = 395 cents
10x+500-25x=395
-15x=-105
x=7 (number of dimes)
20-x=13 (number of quarters)
Cheers,
stan H.

Answer by joyofmath(189) About Me  (Show Source):
You can put this solution on YOUR website!
Merlin has 20 coins in quarters and dimes. The total value of the coins is $3.95. How many coins of each kind does he have?
Merlin has some quarters, Q, and some dimes, D. Q%2BD=20 because he has 20 coins.
The total values is 395 so 25Q%2B10D=395.
Since Q%2BD=20 D=20-Q.
So, 25Q%2B10%2820-Q%29+=+395 or 25Q%2B200-10Q+=+395
Or, 15Q%2B200=395
Or, 15Q=195.
So, Q=13 and D must = 7 since there are 20 coins in total.
Verify: 13%2A25%2B7%2A10+=+325%2B70+=+395.