999.3-998.2+997.3-996.2+995.3-994.2+.+3.3-2.2+1.3-0.2
=(999.3-998.2)+(997.3-996.2)+(995.3-994.2)+...+(3.3-2.2)+(1.3-0.2)
=1.1+1.1+1.1+...+1.1+1.1
=1.1x(1000÷2)
=550
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请点击“采纳为满意答案”!
999.3-998.2+997.3-996.2+995.3-994.2+.+3.3-2.2+1.3-0.2
=(999.3-998.2)+(997.3-996.2)+(995.3-994.2)+...+(3.3-2.2)+(1.3-0.2)
=1.1+1.1+1.1+...+1.1+1.1
=1.1x(1000÷2)
=550
----------------------
请点击“采纳为满意答案”!