Diameter 46141

The road roller has a diameter of 1.4 m and a length of 160 cm
(a) how many square meters the road rolls when it turns 95 times
b) how many times does it turn when rolling a 3 km-long section

Correct answer:

a =  668.5309 m²
b =  682

Step-by-step explanation:

$$\begin{gathered} D=1.4\text{m} \\ l=160\text{cm}\to \text{m}=160:100\text{m}=1.6\text{m} \\ n=95 \\ o=\pi \cdot D=3.1416\cdot 1.4\doteq 4.3982\text{m} \\ {S}_1=o\cdot l=4.3982\cdot 1.6\doteq 7.0372{\text{m}}^2 \\ a=n\cdot S_1=95\cdot 7.0372=668.5309{\text{m}}^2 \end{gathered}$$

$$\begin{gathered} s=3\text{km}\to \text{m}=3\cdot 1000\text{m}=3000\text{m} \\ b=s/o=3000/4.3982=682 \end{gathered}$$

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