If the volume of a sphere is 2304pi, then what is the diameter?

My teacher requires work to be shown. If you can show work, if it's not too much trouble, please do!!! thank you!!!

2 Answers
Mar 3, 2017

The diameter is 24.

Explanation:

The formula for volume of a sphere is:

V=4/3pir^3

Since we know the volume, and have to find the diameter (twice the radius), we need to determine the radius first.

Hence, using the given data:

2304pi=4/3pir^3

We can cancel pi from each side.

2304=4/3r^3

Multiply both sides by 3/4.

2304xx3/4=3/4xx4/3r^3

2304xx3/4=(cancel3)/(cancel4)xx(cancel4)/(cancel3)r^3

2304xx3/4=r^3

576cancel2304xx3/(cancel4)=r^3

576xx3=r^3

To find the cube root, we separate the factors of the number on the left.

3*3*3*4*4*4=r^3

(3*4)(3*4)(3*4)=r^3

12xx12xx12=r^3

12=r

Since the radius (r) is 12, the diameter, which is 2r, will be:

2xx12=24

Mar 3, 2017

24

Explanation:

Vol sphere= 4/3pir^3

:.4/3color(red)pir^3=2304color(red)pi

divide L.H.S and R.H.S by color(red)pi

:.4/3r^3=2304

divide L.H.S and R.H.S by color(red)4/color(red)3

:.(4/3r^3)/color(red)(4/3)=2304/color(red)(4/3)

:.cancel4^1/cancel3^1r^3 xx cancel 3^1/cancel4^1=cancel2304^576/1 xx 3/cancel4^1

:.r^3=576 xx 3

:.r^3=1728

:.r=root3(1728)

:.r=root3(3*3*3*4*4*4

:. color(red)(root3 (3) xx color(red)( root 3color(red)(3) xx root 3 (3) = 3
:.color(red)(root 3(4) xx root 3(4) xx root 3 (4) = 4

:.r=3 xx 4

:.r=12

:.color(red)(Diametercolor(red)= 12 xx 2=24