Apricot peach purchase

We paid a total of 85 crowns for the purchase of 2.5 kg of apricots and 1.5 kg of peaches. A kilogram of peaches is CZK 2 cheaper than a kilogram of apricots. How much CZK was paid for the apricots?

Final Answer:

x =  55 Kc

Step-by-step explanation:

$$\begin{gathered} 2.5a+1.5b=85 \\ b=a-2 \\ 2.5\cdot a+1.5\cdot b=85 \\ 2.5a+1.5b=85 \\ a-b=2 \\ Row2-\frac{1}{2.5}\cdot Row1\to Row2 \\ -1.6b=-32 \\ b=\frac{-32}{-1.6}=20 \\ a=\frac{85-1.5b}{2.5}=\frac{85-1.5\cdot 20}{2.5}=22 \\ a=22 \\ b=20 \\ x=2.5\cdot a=2.5\cdot 22=55\text{Kc} \end{gathered}$$

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