Question

the ratio of total surface area to the lateral surface area of a cylinder whose radius is 20 cm and height 60 cm is

Answer 1

Lateral surface area=(2πrh)
TOTAL surface area=2πr(h+r)
Radius =20cm
Height=60cm
Ratio=total surface area:Lateral surface area
=(2πrh):2πr(h+r)
=2(π×20×60):2×π×20(60+20)
=2400π:3200π
Now=2400π/3200π
=3/4
Ratio=3:4
Thanks