((6 2/3 + 2 4/15+ 5 1/2) : 1/15 - 30 : 5/28) : 2 3/4 =

Question

((6 2/3 + 2 4/15+ 5 1/2) : 1/15 - 30 : 5/28) : 2 3/4 =

Answer 1

=((20/3+34/15+11/2)×15/1-30×28/5)÷11/4=
=((200/30+68/30+165/30)×15-168)×4/11=
=(433/30×15-168)×4/11=(433/2-168)×4/11=
=(216 1/2-168)×4/11=48 1/2×4/11=
=97/2×4/11=194/11=17 7/11