Odometer

The odometer is driven by the wheel's rotation, which has a diameter of 65 cm. After how many rotations does the wheel turn counter to the next kilometer?

Correct answer:

n =  489.7

Step-by-step explanation:

$$\begin{gathered} D=65\text{cm}\to \text{m}=65:100\text{m}=0.65\text{m} \\ x=1\text{km}\to \text{m}=1\cdot 1000\text{m}=1000\text{m} \\ o=\pi \cdot D=3.1416\cdot 0.65\doteq 2.042\text{m} \\ n=x/o=1000/2.042=489.7 \end{gathered}$$

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