2. Two marks example problems I

1. A cylindrical drum has a height of \(20 \ cm\) and base radius of \(14 \ cm\). Find its curved surface area and the total surface area.

 

Answer:

 

Curved surface area \(=\) 176029921232088 \(cm^2\)

 

Total surface area \(=\) 29926160176012320 \(cm^2\)

 

 

2. The curved surface area of a right circular cylinder of height \(14 \ cm\) is \(88 \ cm^2\). Find the diameter of the cylinder.

 

Answer:

 

The diameter of the cylinder \(=\) \(4\)\(2\)\(3\)\(1\) \(cm^2\)

 

 

3. A garden roller whose length is \(3 \ m\) long and whose diameter is \(2.8 \ m\) is rolled to level a garden. How much area will it cover in \(8\) revolutions?

 

Answer:

 

Area covered in \(8\) revolutions \(=\)  \(m^2\)