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40 votes
40 votes
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

User Smartmarkey
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1 Answer

22 votes
22 votes
Step-by-step 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.

User Yurkevich
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