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A sphere with a radius of 2 inches weighs 4.40 pounds. How much does a sphere with a radius of 3 inches weigh?

User Heru S
by
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1 Answer

4 votes
solve for volume
volume of sphere=4/3 times pi tiemes radius^3
radius=2
subsitute
volume=4/3 times pi times 2^3
volume=4/3 times pi times 8
volume=32/3 times pi
to keep the exactness of the number, keep it like that and don't aprox pi to 3.14

also fid the volume of the 3 inch spheree
4/3 times pi times 3^3
4/3 times pi times 27
108/3 times pi
36pi


so the ratio is
32/3pi to 4.40=36pi to x
make fraction
(32/3pi)/4.4=(36pi)/x
multiply both sides by x
(32/3pix)/4.4=(36pi)
multiply both sides by 4.4 to clear fraction
32/3pix=158.4pi
multiply both sides by 3/32
pix=475.2/32pi
simplify
pix=14.85pi
divide both sides by pi
x=14.85
answer is 14.85 pounds

User Rwalter
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8.1k points