计算下列各题：(1)125(40+8); (2)(100-4)(3)2004 (4)125792。
解答：
(1)125(40+8)
=12540+1258
=5000+1000
=6000;
(2)(1)125(40+8)
=12540+1258
=5000+1000
=6000;
(3)200425
=(2000+4)25
=200025+425
=50000+100
=50100;
(4)125792
=125(800-8)
=125800-1258
=(1258)100-1000
=1000100-1000
=1000(100-1)
=99000