题目内容
4.找出下面题中的错误,并改正过来.(1)524-(375+625÷25)
=524-(1000÷25)
=524-40
=484
订正:524-(375+625÷25)
=524-(375+25)
=524-400
=124;
(2)(37-555÷15)×5
=(37-37)×5
=1×5
=5
订正:(37-555÷15)×5
=(37-37)×5
=0×5
=0;
(3)[200-(74+36)]÷2
=[126+36]÷2
=162÷2
=81
订正:[200-(74+36)]÷2
=[200-110]÷2
=90÷2
=45..
分析 (1)运算顺序错误,应先算括号里的除法,再算加法,最后算减法;
(2)计算错误,37-37=0,37-37=1错误;
(3)运算顺序错误,应先算小括号里的加法,再算减法,最后算除法.
解答 解:(1)订正:524-(375+625÷25)
=524-(375+25)
=524-400
=124;
(2)订正:(37-555÷15)×5
=(37-37)×5
=0×5
=0;
(3)订正:[200-(74+36)]÷2
=[200-110]÷2
=90÷2
=45.
故答案为:524-(375+625÷25)
=524-(375+25)
=524-400
=124;
(37-555÷15)×5
=(37-37)×5
=0×5
=0;
[200-(74+36)]÷2
=[200-110]÷2
=90÷2
=45.
点评 考查了整数四则混合运算,注意运算顺序和运算方法.
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