A-A+
下面各题 怎样简便就怎样算.39÷7+31×170.625×36+38×36-3649÷[(
问题详情
39÷7+31×
0.625×36+
参考答案
(1)39÷7+31×17,
=(39+31)×17,
=70×17,
=10;
(2)0.625×36+38×36-36,
=(0.625+0.375-1)×36,
=0×36,
=0;
(3)49÷[(56-12)+(59-518)],
=49÷[13+518],
=49÷1118,
=811;
(4)20082009×2008-2007,
=20082009×2009-20082009×1-2007,
=2008-20082009-2007,
=1-20082009,
=12009;
(5)12+16+112+120+130+142+156+172,
=1-12+12-13+13-14+14-15+15-16+16-17+17-18+18+18-19,
=1-19,
=89;
(6)(29+527)×27×9,
=29×72×9+527×27×9,
=144+45,
=189.
考点: