a)
(65/195+108/324+122/366)*(24/168-6/42)=
=(21060/63180+21060/63180+122/366)*(24/168-6/42)=
=(42120/63180+122/366)*(24/168-6/42)=
=(15415920/23123880+7707960/23123880)*(24/168-6/42)=
=(23123880/23123880)*(1008/7056-1008/7056)=
=1*0=0
b)
=270/63*(16/5+106/15-7/3)=
=270/63*(48/15+106/15-35/15)=
=270/63*119/15=
=32130/945=34