Find the area of the chart paper used to make the curved surface of a model of cylindrical kaleidoscope of length `25` cm and radius `3.5` cm

Explanation

For the given cylindrical kaleidoscope, we have radius of the base, r = 3.5 cm and height, h = 25 cm
Area of the chart paper required
= curved surface area of the kaleidoscope
`= (2pi rh) cm^(2)`
`= (2 xx (22)/(7) xx 3.5 xx 25) cm^(2)`
`= (2 xx (22)/(7) xx (35)/(10) xx 25) cm^(2) = 550 cm^(2)`