9 1/2 = (2*9+1)/2 = 19/2 → (12:2*19)/12 = 114/12
5 1/3 = 16/3 → (12:3*16)/12 = 64/12
6 3/4 = 27/4 → (12:4*27)/12 = 81/12
8 5/6 = 53/6 → (12:6*53)/12 = 106/12
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Если надо привести к смешанным дробям со знаменателем 12,то:
9 1/2 = 9 + (12:2*1)/12 = 9 6/12
5 1/3 = 5 + (12:3*1)/12 = 5 4/12
6 3/4 = 6 + (12:4*3)/12 = 6 9/12
8 5/6 = 8 + (12:6*5)/12 = 8 10/12