(1)4x+1.5=4.2,
4x+1.5-1.5=4.2-1.5,
4x=2.7,
4x÷4=2.7÷4,
x=0.675;
(2)x:4=
1
3 :
1
4 ,
1
4 x=4×
1
3 ,
1
4 x=
4
3 ,
1
4 x×4=
4
3 ×4,
x=
16
3 .
(1)4x+1.5=4.2,
4x+1.5-1.5=4.2-1.5,
4x=2.7,
4x÷4=2.7÷4,
x=0.675;
(2)x:4=
1
3 :
1
4 ,
1
4 x=4×
1
3 ,
1
4 x=
4
3 ,
1
4 x×4=
4
3 ×4,
x=
16
3 .