Question

HELP MEH!!! A cylinder has a height of 1.2 cm and 5mm base radius.If all the dimensions of the cylinder are tripled, what will be its new volume?2,826 mm38,478 mm325,434 mm32,543.4 mm3

Answer 1

Explanation

We have a cylinder with a height of 1.2 cm and a base radius of 5 mm and we must find the volume of a cylinder whose dimensions are three times those of the original one. Therefore this new cylinder has a height of 3*1.2 cm = 3.6 cm and a base radius of 3*5 mm = 15 mm. Before continuing we should write the height of the cylinder in millimeters so we must multiply it by 10 since there are 10 mm in 1 cm:

$3.6\text{ cm}=3.6\cdot10\text{ mm}=36\text{ mm}$

Then the new cylinder has a height of 36 mm and a base radius of 15 mm. The volume of a cylinder with a height h and a base radius r is given by the following formula:

$V=h\cdot\pi r^2$

Then the volume of the cylinder that we are looking for is:

$\begin{gathered} V=36\text{ mm}\cdot\pi\cdot(15\text{ mm})^2 \\ V=25434\text{ mm}^3 \end{gathered}$Answer

Then the answer is the third option: 25,434 mm3.