Question 14681
For 3 days, huh?

1)  Convert the diameters to km using the given 1 mile = 1.61 km.

Earth's equatorial diameter: 7,923 miles = 7,923 miles(1.61 km/mile) = 12,756 km.
Jupiter's equatorial diameter: 88,944 miles = 88,944 (1.61 km/mile) 143,200 km.

2) Volume of a sphere: {{{V = (4/3)pi*r^3}}}

Volume of the earth: {{{V = (4/3)*pi*(12756/2)^3}}} Radius = (1/2)diameter. Use:{{{pi = 3.14}}}
{{{V = 1.0862303407*10^12}}} km cubed.

Volume of Jupiter: {{{V = (4/3)*pi*(143200/2)^3}}}

See if you can work this out yourself. 

When you have found the volume of Jupiter, divide this number by the volume of the earth to find out how many earths will fit inside Jupiter.

Good luck!