333…(99个3)×333…(98个3)9999×7777+3333×6666765×213÷27+765×327÷2741.2×8.1＋11×1.25＋537×0.193.6×31.4＋43.9×6.412.5÷3.6－7÷9＋8.3÷3.6这些都是奥林匹克题，

Answer 1

333…(99个3)×333…(98个3)
=999…(99个9)×111…(98个1)
=100 …(99个0)×111…(98个1)-111…(98个1)
=111…(98个1)00…(99个0)-111…(98个1)
=111…(97个1)0988…(97个8)9
9999*7777+3333*6666
=9999*7777+9999*2222
=9999*9999
=(10000-1)^2
=100000000-20000+1
=99980001
765×213÷27+765×327÷27
=765÷27×(213+327)
=15300
41.2×8.1＋11×1.25＋537×0.19
=41.2*8.1+11*1.25+53.7*1.9
=41.2*8.1+11*1.25+41.2*1.9+12.5*1.9
=41.2*8.1+11*1.25++41.2*1.9+19*1.25
=41.2*(8.1+1.9)+1.25*(11+19)
=41.2*10+1.25*30
=412+37.5=449.5
3.6×31.4＋43.9×6.4
=3.6*31.4+(31.4+12.5)*6.4
=(3.6+6.4)*31.4+12.5*8*0.8
=314+80=394
12.5÷3.6－7÷9＋8.3÷3.6
=12.5/3.6-7*2.5*0.4*9+8.3/3.6
=(12.5-17.5+8.3)/3.6
=11/12