一个是:0.28×8.6+7.2×0.86 还有一个是:999×778+333×666

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/17 13:38:09
一个是:0.28×8.6+7.2×0.86还有一个是:999×778+333×666一个是:0.28×8.6+7.2×0.86还有一个是:999×778+333×666一个是:0.28×8.6+7.2

一个是:0.28×8.6+7.2×0.86 还有一个是:999×778+333×666
一个是:0.28×8.6+7.2×0.86
还有一个是:999×778+333×666

一个是:0.28×8.6+7.2×0.86 还有一个是:999×778+333×666
0.28×8.6+7.2×0.86
=0.28×8.6+0.72×8.6
=(0.28+0.72)×8.6
=1×8.6
=8.6
999×778+333×666
=999×778+999×222
=999×(778+222)
=999×1000
=999000

0.28*(8.6*0.1)+(7.2*0.1)*0.86
=0.28*0.86+0.72*0.86
=(0.28+0.72)*0.86
=0.86
第一题

0.28×8.6+7.2×0.86
=0.28×8.6+0.72×8.6
=(0.28+0.72)×8.6
=8.6
999×778+333×666
=999×778+999×222
=999000