25%x=20 x = 20 × 100 / 25 = 80 x+35%x = 540 135%x = 540 x = 540 × 100 / 135 = 400 x-78%x = 88 22%x = 88 x = 88 × 100/22 = 400
{(35-x)+20}*2=20+x; {55-x}*2=20+x; 110-2x=20+x; 3x=90; x=30
x=10/3
(35-x+20)×2=20+x 这题目吗