每个问题都要有一个必要的计算过程。① 23× 2424-24× 2323 ② 52.44× 79.45+159× 47.56+79.55× 52.44 ③ 18× 3.

=23×24×101-24×23×101

=0;

②52.44×79.45+159×47.56+79.55×52.44

=52.44×(79.45+79.55)+159×47.56

=52.44×159+159×47.56

=159×(52.44+47.56)

=159×100

=15900;

③ 18× 3 7 +0.65× 8 13 - 2 7 ×18+ 5 13 ÷1 7 13

= 54 7 + 2 5 - 32 7 + 1 4

=( 54 7 - 32 7 )+( 2 5 + 1 4 )

=3 1 7 + 13 20

=3 111 140 ;

④ 2.75+ 5 12 -1.4+2 1 4 ÷ 5 12 -87.5%

=2.75+ 5 12 -1.4+5.4-87.5%

=3 1 6 -1.4+5.4-87.5%

=3 1 6 +4-87.5%

=6 7 24 ;

⑤ 2010×2008+1 2009 + 2009+2010×2008 2009×2010-1

= 2009×2008+2008+1 2009 + 2009+2008×2009+2008 2009×(2009+1)-1

= 2009×(2008+1) 2009 + 2009×(2008+1)+2008 2009×2009+2008

=2009+1

=2010.