Salary

Operatér needs to pay 2560 euros using banknotes of 20 EUR and 500 EUR. The total number of banknotes is 8. How many of each denomination are there?

Final Answer:

x =  3
y =  5

Step-by-step explanation:

$$\begin{gathered} 20x+500y=2560 \\ x+y=8 \\ 20\cdot x+500\cdot y=2560 \\ 20x+500y=2560 \\ x+y=8 \\ Row2-\frac{1}{20}\cdot Row1\to Row2 \\ -24y=-120 \\ y=\frac{-120}{-24}=5 \\ x=\frac{2560-500y}{20}=\frac{2560-500\cdot 5}{20}=3 \\ x=3 \\ y=5 \end{gathered}$$

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