Question

find the ratio of total surface area and curved surface area of a cylinder whose height and rTius are7.5 cm and 3.5cm respectivel​

Answer 1

Step-by-step explanation:

total surface area of cylinder = 2πr(h + r)

curved surface Area of cylinder =

2πrh

we have given, height = 7.5 cm

and radius = 3.5 cm

= [2π r ( h + r)] / [ 2πrh ]

= [ 2 x ( 3.14 ) ( 7.5 + 3.5)]

/ [2 x (3.14 ) x ( 7.5 )]

= [ 2 x ( 3.14 ) x 11 ] /[ 2 x (3.14 ) x(7.5)]

= [ 2 x 11 ] / [ 2 x 7.5 ]

= 22 / 15

Answer 2

Answer:

Step-by-step explanation:

Given :-

Radius = 3.5 cm

Height = 7.5 cm

To Find :-

Ratio of total surface area and curved surface area of a cylinder.

Formula to be used :-

2πrh and 2πr(h+r)

Solution :-

Curved Surface Area of cylinder = 2πrh

= 2 × 22/7 × 3.5 × 7.5

= 165 cm²

Total Surface Area of cylinder = 2πr(h+r)

= 2  × 22/7 × 3.5(3.5+7.5)

= 242 cm²

Ratio of Total Surface Area of cylinder : Ratio of Curved Surface Area of cylinder

= 242 : 165

= 22 : 15

Hence, the ratio of total surface area and curved surface area of a cylinder whose height and radius are 7.5 cm and 3.5 cm is 22 : 15.