4x-2.4*4=25.6
x-2.4=6.4
x=8.8
(x-8)/2.4=12
x-8=28.8
x=36.8应该要5部4x-2.4*4=25.64x-2.4*4=4*6.4x-2.4=6.4x=6.4+2.4x=8.8(x-8)/2.4=12 x-8=12*2.4x-8=28.8x=28.8+8x=36.8