57.4:4+1 1/6:4 2/3-(2.7+5 1/20)*0.8/2 1/5-(1 2/3+1/5)

57.4:4+1 1/6:4 2/3-(2.7+5 1/20)*0.8/2 1/5-(1 2/3+1/5)=
<span>14,35+7/6:14/3-(2.7+5,05)*0.8/ 11/5-(1 10/15+3/15)=</span><span>
14,35+7/6*3/14-7,75*0.8*5/11-1 13/15=
</span>14,35+7/2*1/14-31/11-1 13/15=
14,35+1/2*1/2-2  9/11-1 13/15=<span>
14,35+1/4-2  135/165-1 143/165=
</span>14,35+0,25-3  278/165=14,6-4  113/165=
=10,6-113/165=10 6/10-113/165=10 3/5<span>-113/165=10 99/165-113/165=10-14/165

=9 151/165

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