1、(-25/12)÷(-5/3)x4/5 2、(-1 又3/2)÷(-5/3)÷(-0.25) 3、(-3一1又2/1)÷[3又4/3÷(2一3又3/1)x1又5/1] 4、(5/6一10/1一15/8)÷(-5/6)
(-25/12)÷(-5/3)x4/5 =25/12x3/5x4/5=1
(-1 又3/2)÷(-5/3)÷(-0.25) =-3/5÷-5/3x4=3/5x3/5x4=9/100=11又9/1
(-3一1又2/1)÷[3又4/3÷(2一3又3/1)x1又5/1] =(-4又2/1)÷[4/15÷(-3/4)x5/6=2/9÷(4/15x4/3x5/6)=2/9x27/8=3/4
(5/6一10/1一15/8)÷(-5/6)=(30/36-30/3-30/16)÷(-5/6)=30/17x(-6/5)=-36/17