7.5*23+31*2.5简便运算 0.79*0.46+7.9*0.24+11.4*0.079的简便运算

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/29 22:32:33

7.5*23+31*2.5简便运算 0.79*0.46+7.9*0.24+11.4*0.079的简便运算
7.5*23+31*2.5简便运算 0.79*0.46+7.9*0.24+11.4*0.079的简便运算

7.5*23+31*2.5简便运算 0.79*0.46+7.9*0.24+11.4*0.079的简便运算
7.5*23+31*2.5
=2.5*3*23+31*2.5
=2.5*69+31*2.5
=2.5*(69+31)
=2.5*100=250
0.79*0.46+7.9*0.24+11.4*0.079
=0.79*0.46+0.79*2.4+0.79*1.14
=0.79*(0.46+2.4+1.14)
=0.79*4
=3.16

7.5*23+31*2.5=2.5*3*23+2.5*31=2.5*69+2.5*31=2.5*(69+31)=2.5*100=250
0.79*0.46+7.9*0.24+11.4*0.079=0.79*0.46+0.79*2.4+0.79*1.14=0.79*(0.46+1.14+2.4)=0.79*4=3.16

(1)
7.5*23+31*2.5
=7.5*23+23*2.5+8*2.5
=23*(7.5+2.5)+20
=230+20
=250
(2)0.79*0.46+7.9*0.24+11.4*0.079
=0.79*(0.46+2.4+1.14)
=0.79*4
=3.16

甲、乙两数的差是7.02,甲数的小数点向右移动一位就等于乙数。甲、乙两数分别是多少???