volumne

a cuboid 10 metres long, 3 metres wide and 1 metre high has the same surface area as a cube, find the volume of the cube

thanks :smile:

Reply 1

SunGod87

10*3*1 = 30
Surface area of a cube = 6*surface area of one face
30/6 = 5
Each face has an area 5
Each length must therefore be root(5)
Volume of cube = [root(5)]^3
Volume of cube = 5root(5)

Reply 2

arsenalfan.

if you do 10*3*1 isnt it volume? not s.a?

Reply 3

Esquire

wrong above btw.
(10x3)x2+(10x1)x2+(1x3)x2=SA of cuboid.
=86
so... let x=sidelength of cube
6x^2=86
x^2=86/6
x=rt(86/6)
volume=x^3
x^3=(86/6)rt(86/6)
x^3=54.3 (to 3sf)