(1)92.3-55.51+4.49
=36.79-4.49,
=32.3;
(2)6.52+1.43+8.57+3.48
=(6.52+3.48)+(1.43+8.57),
=10+10,
=20;
(3)75.8-13.57-1.43
=75.8-(13.57+1.43),
=75.8-15,
=60.8;
(4)39×89+39×12-39
=(89+12-1)×39,
=100×39,
=3900;
(5)5208÷(31×56)
=5208÷1736,
=3;
(6)(2657+35×26)÷29
=(2657+910)÷29,
=3567÷29,
=123.