( 1 - 1\4 + 3\8 ) : 3\4 - 1\2=(8-2+3)/8:3/4-1/2=9/8·4/3-1/2=3/2-1/2=1
( 1 7\8 + 7 \ 10 ) : 3\8 - 2\5 = 1 (35+28)/40:3/8-2/5= 1 63/40:3/8-2/5=103/40·8/3-2/5=103/15-2/5=97/15=6 7/15
2 *1 5 \12 + 4 * 1\8 + 1 1\9 * 1 1\4 = 2·17/12+1/2+10/9·5/4=17/6+1/2+25/18=2 5/6+1/2+ 1 7/18=3 31/18= 4 13/18
( 1\6 + 1 \10 + 1\15 ) : ( 3\5 - 1\3 - 1\4) = (5+3+2)/30 : (36-20-15)/60=10/30·60=20
( 3 -1 5\8 ) * ( 4 - 1 3\11 ) : (5 - 1 1\4) = (2-5/8)·(3-3/11):(4-1/4)=1 3/8·2 8/11:3 3/4=11/8·30/11·4/15=1