question to long wrote it in ge description

Question

Pierre needs to use a water filled roller to help compact his soil for lawn. The roller is 90cm wide with a diameter of 50cm.

 

A) Find the area covered by one revolution

b) find the capacity of water needed to the nearest Liter if Pierre has to fill the roller three quarters full

 

Answer 1

A.  The roller is a right circular cylinder.  The area covered by one revolution is the lateral surface area of the cylinder.

 

      Area = 2πrh = 2π(25 cm)(90 cm) = 4500π cm²

 

B.  Capacity = (3/4)(Volume) = (3/4)(πr²h) = (3/4)(25 cm)²(90 cm)π 

 

                                                                = 42187.5π cm³(1 liter / 1000 cm³)

 

                                                                = 42.1875π liters