Question

Two open cylinders have the same radius but one is twice as long as the other.

a) Calculate the volume of the two cylinders and compare them using a final statement (sentence).
b) Calculate the surface area of the two cylinders and compare them using a final statement (sentence). If you notice a relationship between volume and surface area,add it to your final
statement. (God bless anyone who can help me ).
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Answer 1

shown below

Explanation:

a) V = h(pi)r²

let x = height

and c = the constant radius

V1 = 2x(pi)c²

V2 = x(pi)c²

let c = random number, such as 2

let x = 3

2x(pi)4

x(pi)4

pi(4) = 12.57

3 x 12.57 = 37.7

6 x 12.57 = 75.4

We can compare these ans realise that the cylinder with double the height will also have double the volume.

b) SA = h(pi)2c

SA1 = 2x(pi)2c

SA2 = x(pi)2c

let c = 2

let x = 3

2(3)(pi)(2(2))

6(pi)4

24(pi)

3(pi)(2)(2)

3(pi)(4)

12(pi)

I don't need to finish the calulation to see that this is also halved. So the surface area of the one with the double length is twice the surface area of the one with a smaller height.

Comparatively, both the volume and surface area are doubled when the height is doubled.

QED.