55 29/33 - 32 29/33 - 6 3/4 : 27 ×7 5/7 - 20 5/21 +1 2/3 =

55 29/33 - 32 29/33 - 6 3/4 ÷27 ×7 5/7 - 20 5/21 +1 2/3 = 2 1/2
1/4×7 5/7=1/4×54/7=27/14 = 1 13/14
55 29/33-32 2933=1844/33  -  1085/33 = 759/33 = 23
23-1 13/14=23/1-27/14=(23 × 14  -  27 × 1)/14 = 322/14  -  27/14 =  295/14 = 21 1/14
21 1/14 - 20 5/21=295/14  -  425/21 =(295 × 3  -  425 × 2)/42 = 885/42  -  850/42 =  35/42 = 5/6
5/6+1 2/3=5/6+5/3=(5 × 1  +  5 × 2)/6 = 5/6  +  10/6 =  15/6 = 5/2 = 2 1/2