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14.
63×67=4221,91×99=9009,
规律:
(10b+a)×(10c+a)
=100bc+10ab+10ac+a
=100bc+10a(b+c)+a
=100bc+100a+a
=100(bc+a)+a
http://m.ksjqmj.com/buchongxitidaan/17790.html
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05网免费提供各类练习与测试答案,请牢记零五网网址:05W.CC
14.
63×67=4221,91×99=9009,
规律:
(10b+a)×(10c+a)
=100bc+10ab+10ac+a
=100bc+10a(b+c)+a
=100bc+100a+a
=100(bc+a)+a
http://m.ksjqmj.com/buchongxitidaan/17790.html
推荐访问