11/2 x 2 10/13 + 2 10/13 x 2 10/13 - 2 10/13 x 3 1/6 =

=2 10/13×(1 1/2+2 10/13- 3 1/6)=
=36/13×(3/2+36/13-19/6)=
=36/13×(102/78+216/78 - 247/78)=
=36/13×71/78=2556/1014=2 528/1014=
=2 264/507
если нигде не ошиблась то так

2 10/13(1 1/2+2 10/13-3 1/6)=2 10/13× (3/2+36/13-19/6)=36/13 ((117+216-247)/78)=36/13(86/78)= 36/13(43/39)=(36×43)/(13×39)= (12×43)/(13×13)=516/169= 3 9/169
проверь условие