Question

The diameter of a garden roller is $0.7$ m and it is $2$ m long. How much area will it cover in $10$ revolutions.

• A. $44m^2$
• B. $88m^2$
• C. $96m^2$
• D. None

Answer 1

The correct option is B $88m^2$

Distance covered in one revolution $=2\pi r=2\pi \left(0.7\right)$

Distance covered in ten revolution $=10\left(2\pi r\right)=10\times 2\pi \left(0.7\right)=l$

Area covered will be $l\times b$

$=10\times 2\pi \left(0.7\right)\times 2$

$=10\times 2\times \frac{22}{7}\times \frac{7}{10}\times 2$

$=88m^2$