-3/5-1/5= - 4/5

-1/3-2/3= - 3/3= - 1

-1/4-5/7 = - 7-20/28= - 27/28

-5/6-1/3=(-5-2)/6=-7/6= - 1  1/6

-4 3/8-3 1/4= - 7 5/8

-6 1/2-3 5/7= - 9 17/14= -10 3/14

-3/7-4/7= - 7/7= -1

-1/8-3/4= - 7/8