(-1/63)÷(1/9-2/7+2/3-1/14) 要简便方法急求!
问题描述：
(-1/63)÷(1/9-2/7+2/3-1/14) 要简便方法急求!
答
(-1/63)÷(1/9-2/7+2/3-1/14)
=(-1/63)/(7/9-5/14)
=(-1/63)/(98-45)/126
=(-1/63)*126/54
=-1/27