8/9×3/4-(5/6-1/4) 3/5+4/5×3/7+6/7

8/9×3/4-(5/6-1/4) =2/3-5/6+1/4=(8-10+3)/12=1/12 3/5+4/5×3/7+6/7=3/5+12/35+6/7=(21+12+30)/35=63/35=1 28/35