how do i solve this equation: 905=4/3 pi r cubed

905  =  (4/3)·π·r³

Multiply both sides by 3:   2715  =  4·π·r³

Divide both sides by 4:    678.75 =  π·r³ 

Divide both sides by π:    216.05  ≈ r³

Find the cube root:                  r  ≈  6.00