Answer: 135cm
Step-by-step explanation
Volume of a cylinder = πr²h
Volume of a cone. = 1/3πr²h
The two shapes are both solid shapes.
Since the have same volume, we can then equate the two together and solve for the height of the cone.
Now make H the height and R the radius of the cylinder and h the height and r the radius of the cylinder.
Now equating the two
πR²H = 1/3πr²h
Now substitute for the values now
Multiply through by 3
3πR²H = πr²h
But π is common so it could be obliterated from the equation
3R²H = r²h
3 x 12² x 20 = 8² x h
3 x 144 x 20 = 64 x h
60 x 144 = 64h
8640. = 64h
Therefore
h = 8640/64
= 135cm
