a) 24/25:(-16/10)-(-14/15):6/5=
=24/25*(-10/16)+14/15*5/6=
=-3/5+1/3=
=-9/15+5/15=
=-4/15
b) (-5/24)*(-36/5)+7/12:(-2 1/3)=
=3/2+7/12:(-7/3)=
=3/2+7/12*3/7=
=3/2+1/4=
=7/4
c) -3/2*12:[-141/4*2]-(-9/2)*15:(33/2*4)=
=-18*(-2/141)+9/2*15:66=
=36/141+135*1/66=
=12/47+45/22=
=22*12+45*47=
=2379