Question

12. If the radius of a cylinder is doubled and the
height is halved. What is the ratio between the
new curved surface area and the previous curved
surface area of the cylinder?​

Answer 1

Step-by-step explanation:

Let radius of base of cylinder be 'r' and height be 'h' CSA of cylinder, S

1

=2πrh

New radius =2r, New height =

2

h

∴ New CSA, S

2

=2π(2r)×

2

h

=2πrh

Now,

S

2

S

1

=

2πrh

2πrh

=1:1

Hope u got the answer

Answer 2

Let radius of base of cylinder be 'r' and height be 'h' CSA of cylinder , S1 =2πrh

New radius = 2r

New height = h/2

therefore,

New CSA , S2 = 2π(2r)×h/2=2πrh

Now ,

S1/S2 = 2πrh/2πrh

→ 1 : 1 ANSWER

....HOPE IT WILL HELP YOU ! ♥️