(九分之七乘十三分之十二+九分之二乘十三分之二)除以十三分之二
=(7/9x6x2/13+2/9x2/13)x13/2
=(42/9+2/9)x2/13x13/2
=44/9
17除以五51+(68分之1+51分之2)乘17
=1/3+1/68x17+2/51x17
=1/3+1/4+2/3
=1+1/4
=5/4
(九分之七乘十三分之十二+九分之二乘十三分之二)除以十三分之二
=(7/9x6x2/13+2/9x2/13)x13/2
=(42/9+2/9)x2/13x13/2
=44/9
17除以五51+(68分之1+51分之2)乘17
=1/3+1/68x17+2/51x17
=1/3+1/4+2/3
=1+1/4
=5/4