write down the equation for calculating the volume of a sphere. this is the equation: v = ⁴⁄₃πr³.
find the radius. if you're given the radius, then you can move on to the next step.
cube the radius.
multiply the cubed radius by 4/3.
multiply the equation by π.
answer:there are 96 wizards
20% of 120 is 24. if you subtract 24 from 120 you get 96