Children carnival tickets

A carnival is organized in the village. The ratio of the price of one child ticket to the price of one adult ticket is 3:4 (in that order).
Two children's tickets and three tickets for an adult cost a total of 270 Sk.
How much will 2 adults and 3 children pay for carnival tickets in total?

Final Answer:

x =  255 Kc

Step-by-step explanation:

$$\begin{gathered} a=3/4\cdot b \\ 2a+3b=270 \\ 2\cdot a+3\cdot b=270 \\ 4a-3b=0 \\ Row2-\frac{2}{4}\cdot Row1\to Row2 \\ 4.5b=270 \\ b=\frac{270}{4.5}=60 \\ a=\frac{0+3b}{4}=\frac{0+3\cdot 60}{4}=45 \\ a=45 \\ b=60 \\ x=2\cdot b+3\cdot a=2\cdot 60+3\cdot 45=255\text{Kc} \end{gathered}$$

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