(1)2x-
3
4 x÷
4
5 =510,
2x-
15
16 x=510,
17
16 x=510,
17
16 x×
16
17 =510×
16
17 ,
x=480;
(2)5:(x-1)=
3
20 :18%,
3
20 ×(x-1)=5×18%,
3
20 ×(x-1)×
20
3 =0.9×
20
3 ,
x-1+1=6+1,
x=7.
(1)2x-
3
4 x÷
4
5 =510,
2x-
15
16 x=510,
17
16 x=510,
17
16 x×
16
17 =510×
16
17 ,
x=480;
(2)5:(x-1)=
3
20 :18%,
3
20 ×(x-1)=5×18%,
3
20 ×(x-1)×
20
3 =0.9×
20
3 ,
x-1+1=6+1,
x=7.