几道简算题99又656/657*4562009*20102010-2010*20092009
问题描述:
几道简算题
99又656/657*456
2009*20102010-2010*20092009
答
99又656/657*456
=(100-1/657)*456
=45600-456/657
=45599又201/657
=45599又67/219
2009*20102010-2010*20092009
=(2010-1)(2010*10001)-2010(2009*10001)
=2010(2010*10001)-2010*10001-2010(2009*10001)
=2010*10001(2010-2009)-2010*10001
=2010*10001-2010*10001
=0