题目

脱式计算(能简便的要用简便方法计算) (1) 36+64×85+15    (2) 0.4×9×25    (3) 61×40%+38× +0.4 (4) 2475÷45+2475÷55 (5) (15﹣14× )× (6) +5.8﹣ +4.2. 答案: 解:36+64×85+15 =36+5440+15=5476+15=5491; 解:0.4×9×25 =0.4×25×9=10×9=90; 解:61×40%+38× 25 +0.4 =61×0.4+38×0.4+0.4=(61+38+1)×0.4=100×0.4=40; 解:2475÷45+2475÷55 =55+45=100; 解:(15﹣14× 47 )× 821 =(15﹣8)× 821 =7× 821 = 83 ; 解: 157 +5.8﹣ 87 +4.2 =( 157 ﹣ 87 )+(5.8+4.2)=1+10=11.
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