(13/42+41/12)-14/7=+(12/6+44/84)-10/12

(13/42+41/12)-14/7+(12/6+44/84)-10/12=145/84+142/84=287/84=41/12=
=3 5/12
1)13/42(*2)+41/12(*7)=26/84+287/84=313/84
2)313/84-14/7(*12)=313/84-168/84=145/84
3)12/6(*14)+44/84=168/84+44/84=212/84
4)212/84-10/12(*7)=212/84-70/84=142/84