Republic

First, guess which circle has the larger diameter: the one with the same area as the area of the Czech Republic, or the one with a circumference equal to the length of the border of the Czech Republic? Then check your guess by calculating. The area of the Czech Republic is 78,864 square kilometres. The total length of the state border is 2,310.4 kilometres.

Final Answer:

D₁ =  735.4232 km
D₂ =  316.8797 km

Step-by-step explanation:

$$\begin{gathered} D_1>D_2 \\ o=2310.4 \\ {D}_1=o/\pi =2310.4/3.1416=735.4232\text{km} \end{gathered}$$

$$\begin{gathered} S_2=78864 \\ {r}_2=\sqrt{S_2/\pi }=\sqrt{78864/3.1416}\doteq 158.4399 \\ {D}_2=2\cdot r_2=2\cdot 158.4399=316.8797\text{km} \end{gathered}$$

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