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Carlos has a box of coins that he uses when playing poker

with friends. The box currently contains 56 coins,
consisting of pennies, dimes, and quarters. The number of
pennies is equal to the number of dimes, and the total
value is $6.59. How many of each denomination of coin
does he have?

User Metakeule
by
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1 Answer

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Answer: hi

We can begin by using algebra to represent the number of coins of each denomination. Let x be the number of pennies and dimes, and y be the number of quarters. Since there are equal number of pennies and dimes, we can write:

x + x + y = 56 (number of coins)

Next, we can use the information about the total value of the coins to set up another equation. We know that the total value is $6.59, and the value of each coin is:

Pennies: $0.01 * x = $0.01x

Dimes: $0.1 * x = $0.1x

Quarters: $0.25 * y = $0.25y

The total value is the sum of the value of each coin:

$0.01x + $0.1x + $0.25y = $6.59

Now we have a system of equations:

x + x + y = 56 and 0.01x + 0.1x + 0.25y = 6.59

We can now solve this system of equations using substitution method.

x + x + y = 56

x = 56 - y

Now we can substitute x in the second equation:

0.01(56-y) + 0.1(56-y) + 0.25y = 6.59

0.56 - 0.01y + 0.56 - 0.1y + 0.25y = 6.59

1.12 - 0.11y = 6.59

-0.11y = -5.47

y = 50

Now that we know the number of quarters, we can substitute it back into the equation x + x + y = 56

x = 6

So Carlos has 6 pennies and dimes, and 50 quarters in the box.

We can check this by multiplying the number of coins by their value and adding up

60.01 + 60.1 + 50*0.25 = 0.06 + 0.6 + 12.5 = 6.59

Explanation:

User Harold Smith
by
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