Math question?

Question

How many more square feet of tile would it take to cover a cube of sides 8 feet than a sphere of diameter 8 feet?

Answer 1

Surface area of a sphere = 4*pi*r^2, where r=d/2 = 4 ft, where d is the diameter, so area = 64*pi = 201.06 sq ft

Surface area of cube = 6*s^2, where s is the side length, or 6*8^2 = 384 sq ft

So, about 183 more sq ft of tile are needed.

Answer 2

Surface Area of a Cube = 6 a^2

Surface Area of a Sphere = 4 pi r^2

For your cube, substitute 8 for a and find your answer.
For your sphere, substitute 4 for r and find your answer (the problem gives you diameter instead of radius)

Subtract your two answers to find what you're looking for.

Answer 3

Personally, I think you would have a real problem trying to apply flat tile to an 8 foot diameter sphere.
cube=384 square feet
sphere=201.0619298 square feet
difference=182.9380702 square feet

Answer 4

Area of Cube = 6 (Area of the square, s1 * s1)
= 6 (8 * 8)
= 384 sq ft.

Area of a Sphere = 4pir^2 where r = 1/2 diameter = 4 ft
= 4*3.14*4^2
= 4*3.14*16
= 200.96 sq ft

384 - 200.96 = 183.04 sq ft

Answer 5

cube has surface area: 6*(8^2)=384
sphere of diameter 8 feet = radius 4 feet. surface area = 4*pi*(r^2)=4*pi*16=64*pi

so difference = 384-(64*pi) approx equal to 183

(i dont have a calculator)!!

Answer 6

Surface area of sphere-surface area of cube
=4*Pi*8^2-6*8^2
=64[4*22/7-6]
=64[12.57-6]
=420.48 sq ft

Answer 7

Hmmm - lots of maths questions, are you by any chance trying to get us to do your homework? Well, I see you have some answers, you betterhope they know what they are talking about! I, on the other hand, couldn't help if I wanted to (which I don't, as that wont help you learn) as I am rubbish at maths.

Naughty! (possibly)