The length of a metallic pipe is 7.56 m. Its external and internal radii are 2.5 cm and 1.5 cm respectively. If 1 cm³ of the metal weight 7.5 g, then the weight of the pipe is: $$\left( {{\text{Take }}\pi = \frac{{22}}{7}} \right)$$

A. 72.82 kg

B. 70.14 kg

C. 71.28 kg

D. 69.68 kg

Answer: Option C

Solution (By Examveda Team)

V = π(R² - r²) × h
V = $$\frac{{22}}{7}$$ × 756(2.5² - 1.5²)
V = 22 × 108 × 4 × 1
V = 9484 cm³
The weight of the pipe
$$\eqalign{ & = \frac{{9484 \times 7.5}}{{1000}} \cr & = 71.28{\text{ kg}} \cr} $$