题目
脱式计算。(能简算的要简算)
(1)
35×40+630÷18
(2)
36.5×25%+0.25×65.5-2×
(3)
7.2×1.25
(4)
答案: 35×40+630÷18 =1400+35 =1435
36.5×25%+0.25×65.5-2×14 =36.5×25%+25%×65.5-2×25% =(36.5+65.5-2)×25% =100×25% =25
7.2×1.25 =9×0.8×1.25 =9×(0.8×1.25) =9×1 =9
16+112+120+130+142 =12-13+13-14+14-15+15-16+16-17 =12-17 =514