Museum entrance fee

The family paid (2 adults and three children) in the museum, and the children spent half the adult entrance fee. How much does the children's entrance fee to the museum cost if Dad paid CZK 315.)

Final Answer:

d =  45 Kc

Step-by-step explanation:

$$\begin{gathered} 2x+3d=315 \\ d=x/2 \\ 2x+3\cdot x/2=315 \\ 2\cdot x+3\cdot x/2=315 \\ 7x=630 \\ x=\frac{630}{7}=90 \\ x=90 \\ d=x/2=90/2=45\text{Kc} \end{gathered}$$

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