Volume of cylinder (1 Viewer)

[nsbrando]

The volume of this cylinder is 330cm^3

What are the dimensions of the cylinder, answer in 2 d.p.

 

[Kat92]

The volume of this cylinder is 330cm^3

What are the dimensions of the cylinder, answer in 2 d.p.

I am not entirely sure whether this is a HSC General maths question or not- as normally you would only solve for one variable.


Anyway, this is what I am thinking:

2 circles + rectangle
A = 2pir2 + 2pirL


V = pir2L
330 = pir2L
L = 330/pir2


A = 2pir2 + 2pir330/pir2
A = 2pir2 + 660/r


A= 4 pir - 660r-2


0 = 4 pir - 660r-2
660r-2 = 4pir
165r-2 = pir
52.52 = r3
r = 3√52.52 = 3.745cm (1dp)


A = 2pi3.7452 + 660/3.745
A = 264.4cm3 (1dp)


Dimensions

Radius
r = 5.5cm (1dp)

Length
L = 330/пr2
L = 330/п3.7452
L = 7.7cm


Hopefully that helps.. Otherwise I guess wait and see whether anyone else has any input into this one!