( 1 1/35 : 4/5 -1 8/35) * 3 1/3 =?
(1 1/35:4/5-1 8/35)*3 1/3= (1 1*5/35*4-1 8/35)*3 1/3= (1 1/28-1 8/35)*3 1/3= (1 5/140-1 32/140)*3 1/3= (-27/140*3 1/3)= -81/420* 3 140/420= 3 -81*140/420=3*(-27)=-81