x/60％ + 4*5/9=x
x/0.6 + 20/9 = x
两边同乘以 9 得
15x + 20 = 9x
6x = -20
x = - 10/3能在帮我解一下吗 x/(x/0.6+4)=5/9,x/(x/0.6+4)=5/99x = 5(x/0.6+4)9x = 50x/6 + 20两边同乘以 6 得54x = 50x + 1204x = 120x = 30