Problema Solution

Erwin has 40 pieces of coins consisting of 5 cents, 10 cents, and 25 cents. The number of 5 cents is equal to the number of 10 cents. If he has a total of 8.25, how many coins of each kind does he have?

Answer provided by our tutors

Let

x = the number of 5 cents

y = the number of 10 cents

z = the number of 25 cents

x + y + z = 40

x = y

5x + 10y + 25z = 825

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click here to see the system of equations solved for x, y and z

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x = 5 coins of 5 cents

y = 5 coins of 10 cents

z = 30 coins of 25 cents

Erwin has 5 coins of 5 cents, 5 coins of 10 cents and 30 coins of 25 cents.