Question

A laser pointer in the shape of a cylinder is 13 centimeters long with a radius of 1 centimeter. On top it has a cone-shaped tip with a height of 3 centimeters. What is the volume of the laser pointer in terms of pi?

Answer 1

We know that

step 1
find the volume of a cylinder

volume of a cylinder=pi*r²*h
where
h=13 cm
r=1 cm
volume of a cylinder=pi*1²*13----> 13*pi cm³

step 2
find the volume of a cone

volume of a cone=(1/3)*pi*r²*h
where
r=1 cm
h=3 cm
volume of a cone=(1/3)*pi*1²*3-----> pi cm³

step 3
find the volume of the laser pointer

volume of the laser pointer=volume of a cylinder+volume of a cone
volume of the laser pointer=13*pi+pi-----> 14*pi cm³

the answer is
volume of the laser pointer is 14*pi cm³