railway RRB NTPC Mock Test Series 2024-25 (CBT 1 + CBT 2) Quantitative Aptitude Mensuration Solid Figures
A solid iron sphere of diameter 6 cm is melted and made into a hollow cylindrical pipe of external diameter 10 cm and of length 4 cm. The thickness of the pipe is:
1
1 cm
2
2 cm
3
4 cm
4
8 cm