The mass of a spherical ball varies as the cube or radius and inversely is the area when the radius is 14,area=821,the mass is 59.4 find (a) the equation connecting the variable (b)when area is 1018 radius is 9cm
m = k r^3/(4π r^2)
m = k/(4π) r
when area = 821
4π r^2 = 821
r^2 = 65.3331..
r = 8.082889... <---- I stored it in memory of calculator
and if m = 59.4
59.4 = k/(4π)*(8.082889..)
k = 92.348....
m = 92.34846/(4π) r
check my arithmetic,
leaving b) up to you , it simply says the radius is 9