(1)0.35x=7,
0.35x÷0.35=7÷0.35,
x=20;
(2)x÷0.2=0.5,
x÷0.2×0.2=0.5×0.2,
x=0.1;
(3)x+0.42=4.2,
x+0.42-0.42=4.2-0.42,
x=3.78;
(4)x-4.6=6.4,
x-4.6+4.6=6.4+4.6,
x=11.
(1)0.35x=7,
0.35x÷0.35=7÷0.35,
x=20;
(2)x÷0.2=0.5,
x÷0.2×0.2=0.5×0.2,
x=0.1;
(3)x+0.42=4.2,
x+0.42-0.42=4.2-0.42,
x=3.78;
(4)x-4.6=6.4,
x-4.6+4.6=6.4+4.6,
x=11.