# The total surface area of a solid right circular cylinder is 231 cm2, itscurved surface is 2rd3 of the total surface area. Find the radius of thebase and height.

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so, its curved surface area is=2/3(231)cm2

2πrh=154 cm2......(2)

putting value of 2πrh from equation (1) in equation (2) we will get

=> 2πr2+154=231

=>2πr2=231-154

=>2πr2=77

=>r2=77/(2π)

=> r2=12.25 (π=22/7)

=> r=(12.25)^(1/2) cm

=> 3.5 cm

If we put the value of r=3.5cm in equation (2) we will get

=> 2πrh=154

=> 2(22/7)*3.5* h=154

=> 22h=154

=> h=154/22 cm

=> 7cm(ans)