如题所述
第1个回答 2014-06-06
解:69×99
=69×(100-1)
=69×100-69×1
=6900-69
=6831
希望我的回答对你有所帮助
=69×(100-1)
=69×100-69×1
=6900-69
=6831
希望我的回答对你有所帮助
第2个回答 2014-06-06
69×99
=69×(100-1)
=69×100-69×1
=6900-69
=6831
=69×(100-1)
=69×100-69×1
=6900-69
=6831
第3个回答 2014-06-06
69X99
=69×(100-1)
=6900-69
=6800+100-69
=6800+31
=6831本回答被网友采纳
=69×(100-1)
=6900-69
=6800+100-69
=6800+31
=6831本回答被网友采纳