Asphalt - rolling

A road roller has a diameter of 80 cm and a width of 1.2 m. How many square metres of road does it roll if it makes twenty full rotations?

Final Answer:

S =  60.32 m²

Step-by-step explanation:

$$\begin{gathered} D=80\text{cm}\to \text{m}=80:100\text{m}=0.8\text{m} \\ a=1.2\text{m} \\ n=20 \\ o=\pi \cdot D=3.1416\cdot 0.8\doteq 2.5133\text{m} \\ {S}_1=o\cdot a=2.5133\cdot 1.2\doteq 3.0159{\text{m}}^2 \\ S=n\cdot S_1=20\cdot 3.0159=60.32{\text{m}}^2 \end{gathered}$$

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