Chemical drum

A cylinder chemical drum is 220.5cm long and the radius of the drum is 42cm. Calculate the cost of painting the drum at the rate of RS.0.15/cm².

Correct answer:

x =  10390.8177 RS

Step-by-step explanation:

$$\begin{gathered} h=220.5\text{cm} \\ r=42\text{cm} \\ {S}_1=\pi \cdot r^2=3.1416\cdot 42^2\doteq 5541.7694{\text{cm}}^2 \\ {S}_2=2\pi \cdot r\cdot h=2\cdot 3.1416\cdot 42\cdot 220.5\doteq 58188.5791{\text{cm}}^2 \\ S=2\cdot S_1+S_2=2\cdot 5541.7694+58188.5791\doteq 69272.118{\text{cm}}^2 \\ x=0.15\cdot S=0.15\cdot 69272.118=10390.8177\text{RS}=1.039\cdot 10^4\text{RS} \end{gathered}$$

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