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19又19分之18*5

来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/17 21:52:38
19又19分之18*5
用简便方法计算
【(+3/5)+(-1/2)+(-5/12)】*60
(-8)*(-12)*(0.125)*(-1/3)*(-1/5)
(-11)*(-2/5)+(-11)*(+2又五分之三)+(-11)*(1/5)
19又18/19×5
=(20-1/19)×5
=20×5-1/19×5
=100-5/19
=99又14/19
再问: 【(+3/5)+(-1/2)+(-5/12)】*60 (-8)*(-12)*(0.125)*(-1/3)*(-1/5) (-11)*(-2/5)+(-11)*(+2又五分之三)+(-11)*(1/5)
再答: [3/5+(-1/2)+(-5/12)]×60 =(3/5-1/2-5/12)×60 =3/5×60-1/2×60-5/12×60 =36-30-25 =-19 (-8)×(-12)×(0.125)×(-1/3)×(-1/5) =8×3×4×1/8×1/3×1/5 =4×1/5 =4/5 (-11)×(-2/5)+(-11)×(2又3/5)+(-11)×(1/5) =(-11)×(-2/5+2又3/5+1/5) =-11×(2又1/5) =-24又1/5