A cylinder has diameter of 4ft and a height of 9ft. Explain whether halving the diameter has the same effect on the surface area as halving the height.

See Below

Step-by-step explanation:

The surface area of cylinder is given by the formula:

Where

r is radius ( diameter is 4, so radius is 4/2 = 2)

h is height ( h = 9)

Lets find original surface are:

Halving diameter:

diameter would be 4/2 = 2, so radius would be 2/2 = 1

So, SA would be:

Halving height:

Height is 9, halving would make it 9/2 = 4.5

Now, calculating new SA:

Original SA is ,

Halving diameter makes it

Halving height makes it

So, halving diameter does not have same effect as halving height.