((3/5+7/20) -22/27(-1/4-2/11 +7/2))/(-3-25/2) +1/2 =
= ((4*3+7)/20) -22/27((-11*1-2*4+ 7*22)/44)/((-6-25)/2)+1/2 =
= ((19/20) -22/27(135/44))/(-31/2) + 1/2 =
= ((19/10) -(135/27))/(-31) + 1/2 =
= ((27*19) -1350)/270)/(-31) + 1/2 =
= ((27*19) -1350)/27)/(-31) + 1/2 =
= (-837/270)/-31 + 1/2 =
= -3.1/-31 + 1/2 =
=1/10 +1/2 = (1 + 5)/10 = 3/5