The length of each edge of a cube is decreased by 40 percent By what percent does the volume of the cube decrease? Express your answer to the nearest tenth.

Answer:78% (to the nearest tenth)Step-by-step explanation:Volume of a cube = (length )³Let the length of the cube = yOriginal volume = y³if the length is decreased by 40%, then new length = 1- (40% of y)                                                                                      = 1-0.4y                                                                                      =  0.6%New volume (after decreasing the length) = (0.6y)³                                                                       =  0.216‬‬y³% Volume decrease = (Original volume - New volume)/Original Volume x 100%                                  =  (y³ - 0.216‬‬y³)/ y³  x 100%                                  = 0.784y³/y³  x 100%                                  =78.4%                                 ≈78%