最好是写在纸上,拍照给我

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/28 01:03:09
最好是写在纸上,拍照给我

最好是写在纸上,拍照给我
最好是写在纸上,拍照给我

最好是写在纸上,拍照给我
(1)(-2)×4/5×(-9/10)×(-2/3)
=-8/5×9/10×2/3
=-36/25×2/3
=-24/25
(2)(-6)×5×(-7/6)×2/7
=-30×(-7/6)×2/7
=35×2/7
=10
(3)(-4)×7×(-1)×(-0.25)
=-28×0.25
=-7
(4)(-5/24)×8/15×(-3/2)×1/4
=1/9×3/2×1/4
=1/6×1/4
=1/24
(5)49又24/25×(-5)
=(50-1/25)×(-5)
=-50×5+1/25×5
=-250+1/5
=-249又4/5
(6)(-8)×(-7.2)×(-2.5)×5/12
=-(8×2.5)×(7.2×5/12)
=-20×3
=-60
(7)-7.8×(-8.1)×0×|-19.6|=0
只要有一个因数是0,结果就是0
(8)-|-0.25|×(-5)×4×(-1/25)
=-(0.25×4)×(5×1/5)
=-1×1/5
=-1/5
(9)(-8)×(1/2-1又1/4+1/8)
=-8×1/2+8×1又1/4-8×1/8
=-4+10-1
=5
(10)(-1/12-1/36+3/4-1/6)×(-48)
=1/12×48+1/36×48-3/4×48+1/6×48
=4+4/3-36+8
=-22又2/3
(11)(-1又1/4)×(-3又4/5)
=5/4×19/5
=19/4
=4.75
(12)-13×2/3-0.34×2/7+1/3×(-13)-5/7×0.34
=-13×(2/3+1/3)-0.34×(2/7+5/7)
=-13×1-0.34×1
=-13-0.34
=-13.34