Question

27 solid spheres each of radius 2 cm are melted to form one solid new sphere what will be the surface area of the new sphere?

Answer 1

volume of smaller sphere= 4/3(pie)r^3
total volume of cubes = 27*4/3(pie)r^3
total volume of spheres = volume of larger sphere
this gives radius of larger sphere = 6cm
surface area= 4(pie)r^2 = 452.57cm^2 (approx) 

Answer 2

Firs find the Total surface area of small sphere and multiply it by 27.
Then your answer will come 678.8. Now do it 2*22/7*r=678.8
r= 678.8*7/2*22 your answer will come r = 107.8cm. then find the TSA of new sphere with the radius 107.8cm