1/20 ×(2,31 :0,77) =
=1/20 ×(231/100 :77/100) =
=1/20 ×231/77 =
=1/20 ×33/11 =
=1/20 ×3 =
=3/20
1,25: 5/4 -3,(3) ori 0,3+0,1(6)=
=125/100 × 4/5 -(33-3)/9 × 3/10+(16-1)/90=
=5/4 × 4/5 -30/9 × 3/10+1/6=
=1 -10/3 × 3/10+1/6=
=1 -1+1/6=
=1/6
(1,5+1/3 ):[0,(6)+6(6)]=
= (15/10+1/3 ):[6/9+(66-6)/9]=
= (3/2+1/3 ):[2/3+20/3]=
=(9+2)/6 x3/22
=11/6 x3/22 =1/4