下面是简便计算6道求解答.急

1.91*十三分之一-1÷13*10+9÷13
=91/13-10/13+9/13
=1/13*(91-10+9)
=90/13
2.125*25*3232*69
=125*25*32**101*69
=125*8*25*4**6969
=1000 00*6969
=696900000
3.567÷567又568分之567
=567/(567+567/568)
=567/[567(1+1/568)]
=1/(569/568)
=568/569
4.131313分之10101*91
=10101*91/131313
=10101*9/(10101*13)
=9/13
5.2006÷2008分之2007
=2006*2008/2007
=(2007^2-1)/2007
=2007-1/2007
=2006又2006/2007
6.231÷231又232分之231
=231/(231+231/232)
=231/[231(1+1/232)]
=1/(1+1/232)
=1/233/232
=232/233 .