Question

78.9×0.9+7.89x10怎么用简便运算？

Answer 1

78.9×0.9+7.89×10
=78.9×(1+1-0.1)
=78.9×2-78.9
=157.8-78.9
=78.9

Answer 2

这个是等于78.9×0.9+78.9×0.1=78.9×(0.9+0.1)=78.9×1=78.9

Answer 3

78.9×0.9+7.89×10
=7.89×9+7.89×10
=7.89×（9+10）
=149.91

Answer 4

用分配率运算简单
=7.89x90+7.89x10
=7.89x（90+10）
=7.89x100
=789

Answer 5

78.9×0.9＋7.89×10
=7.89×90＋7.89×10
=7.89×(90＋10)
=7.89×100
=789