30-23,1:(5 7/20-4 6/35)=
30-231/10:(107/20-146/35)=
30-231/10:33/28=
30-231/10*28/33=
30-7/5*14/1=30-98/5=52/5=10 2/5=10,4
30-23,1:(5 7/20-4 6/35)=
30-231/10:(107/20-146/35)=
30-231/10:33/28=
30-231/10*28/33=
30-7/5*14/1=30-98/5=52/5=10 2/5=10,4