脱式计算 (52-39)×26728-(660+145÷29)(75+360)÷(20-5)300-225÷5+145.
网友回答
解:
(1)(52-39)×26,
=13×26,
=338;
(2)728-(660+145÷29),
=728-(660+5),
=728-665,
=63;
(3)(75+360)÷(20-5),
=435÷15,
=29;
(4)300-225÷5+145,
=300-45+145,
=300+100,
=400.
解析分析:(1)先算减法,再算乘法;(2)先算除法,再算加法,最后算减法;(3)先算加法和减法,再算除法;(4)先算除法,再算减法,最后算加法.
点评:四则运算,先弄清运算顺序,然后再进一步计算即可.