Volume of a Cylinder

The curved surface area of a right circular cylinder of basis radius $r$ is obtained by multiplying its volume by

The radius of a solid right circular cone increases by $20\%$ and its height decreases by $20\%.$ The percentage change in its volume is:

Water flows at the rate of $10 \mathrm{m}$ per minute through a cylindrical pipe with internal diameter $2 \mathrm{cm}$. How long (in minutes) would it take to fill completely a conical vessel whose radius is $50 \mathrm{cm}$ and depth $45 \mathrm{cm}$.

Mark True or False.

1. The length of the iron sheet $11$ cm wide required for making an open cylinder $15$ cm high and$7$ cm as base radius $(\pi =22/7)$ is $74$ cm.
2. The radius of the cylinder is made twice as large. The height be reduced by $25\%$, so that volume remains the same as before?
3. The radii of the two cylinders are in the ratio $2:3$ and their heights are in the ratio $5:3$. The ratio of their volumes is $20 : 27$.
4. If the radius of the base of the right circular cylinder is reduced by $50\%$, keeping the same height then the volume of the new cylinder is $25\%$ of that of the original.

Codes:

If $QR=3PQ$, What portion of the cylinder is empty to that of filling one.

 Given a cylinder and one of its cross-sections parallel to the axis of cylinder. Distance between the cross-section and the axis of the cylinder is $15$ cm, a diagonal of the cross-section is $2\sqrt{89}$cm. The radius of the base is $17$ cm. The volume of the cylinder is $k\pi$. What is the value of $k$?

The Diagonal of an axial cross-section of a cylinder is $20$ cm and makes ${60}^o$ angle with the plane of the base of the cylinder. The volume of the cylinder is $k\pi \sqrt{3}$ cu cm. What is the value of k?

Cotyledons are also called-