Question

A closed cylindrical box 75cm high and base radius 35 cm is to made . How many square metres of sheet metal is ñèéded ? Find the capacity of box .

Answer 1

$\bold \purple{tsa \: \: = \: \: \: 2 \: \pi \: r \: h \: + 2 \: \pi \: {r}^{2} }$

$= > 2 \times \frac{22}{7} \times 35.75 + 2 \times \frac{22}{7} \times 35.35 \\ = > \frac{44 \times 35}{7} (75 + 35) \\ = > 220 \times 110 = {24200m}^{2} \\ = > \frac{242000}{100 \times 100} = 2.42 {m}^{2} \\ \blue{capacity \: of \: box \: = \: \frac{22}{7} \times 35 \times 35 \times {75}^{3} } \\ \boxed{ans = 288750 {cm}^{3} }$