5/11 . 18/29 - 8/11 . 5/29 + 5/29 . 19/11
=5/11x(5/29+13/29)-8/11 . 5/29 + 5/29 . 19/11
=5/11x5/29+13/29x5/11-8/11x5/29+5/29x19/11
=(5/11x5/29+13/29x5/11)-(8/11x5/29-5/29x19/11)
=5/11x(5/29+13/29)-5/29x(8/11-19/11)
=5/11x18/29-5/29x(-1)
=90/319-(-5/29)=5/11