Question

the radius of the base and height of a cylinder are in the ratio 2 ratio 3 if it's volume = 1617 CM cube​

Answer 1

let radius be 2x and height be3x

volume =1617

$\bold{\begin{gathered} \pi {r}^{2} h = 1617 \\ \frac{22}{7} \times 2 {x}^{2} \times 3x = 1617 \\ \frac{22}{7} \times 4 {x}^{2} \times 3x = 1617 \\ \frac{22}{7} \times 12 {x}^{3} = 1617 \\ 12 {x}^{3} = \frac{1617 \times 7}{22 } \\ 12 {x}^{3} = 514.5 \\ {x}^{3} = \frac{514.5}{12} \\ {x}^{3} = 42.875 \\ x = 3.5 \\ \end{gathered} }$

r=3.5×2=7cm

h=3.5×3=10.5cm

Now,

TSA of cylinder = 2πr(r+h)

$</p><p>\begin{gathered}2 \times \frac{22}{7} \times 7(7 + 10.5) \\ = 44 \times 17.5 \\ = 770 {m}^{2} \end{gathered}$