如题所述
第1个回答 2015-07-01
686X101
=686×100+686
=68600+686
=69286
3.7X99+3.7X2
=3.7×(100+1)
=370+3.7
=373.7
68.7一14.5一15.5
=68.7-(14.5+15.5)
=68.7-30
=38.7
=686×100+686
=68600+686
=69286
3.7X99+3.7X2
=3.7×(100+1)
=370+3.7
=373.7
68.7一14.5一15.5
=68.7-(14.5+15.5)
=68.7-30
=38.7