volume ratio math Q

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tRNA

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diameter of sun=864000miles, diameter of earth=8000miles find the approximate ratio of the volume of the sun to the volume of earth?
answer= 1250,000:1

i don't understand what's wrong with my method, why am i not getting the right answer?? this is how i did it

1)vol. of sphere= 4(pi)r^3/3
2) r for sun=432000, earth=4000

3) (4pi(432000)^3/3)/(4pi(4000)^3/3)
4) cancel the 4pi/3 from the top and bottom so your left with
(432000)^3/(4000)^3 which is the same as:
(432000)(432000)(432000)/(4000)(4000)(4000)
5) then after canceling everything you get (18)^3/(1)^3 which is 5832:1

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diameter of sun=864000miles, diameter of earth=8000miles find the approximate ratio of the volume of the sun to the volume of earth?
answer= 1250,000:1

i don't understand what's wrong with my method, why am i not getting the right answer?? this is how i did it

1)vol. of sphere= 4(pi)r^3/3
2) r for sun=432000, earth=4000

3) (4pi(432000)^3/3)/(4pi(4000)^3/3)
4) cancel the 4pi/3 from the top and bottom so your left with
(432000)^3/(4000)^3 which is the same as:
(432000)(432000)(432000)/(4000)(4000)(4000)
5) then after canceling everything you get (18)^3/(1)^3 which is 5832:1

It is your math. 432000/4000=108 not 18.
 
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