题目
脱式计算.
(1)
(320+280)÷50×4
(2)
400﹣(1300÷65+35)
(3)
927÷[630÷(34+36)]
(4)
[300﹣(56+44)]÷25
答案: (320+280)÷50×4 =600÷50×4 =12×4 =48
400﹣(1300÷65+35) =400﹣(20+35) =400﹣55 =345
927÷[630÷(34+36)] =927÷[630÷70] =927÷9 =103
[300﹣(56+44)]÷25 =[300﹣100]÷25 =200÷25 =8