(45968+114712):52+(20229+25719):84=3637
1)45968+114712=160680
2)160680:52=3090
3)20229+25719=45948
4)45948:84=547
5)3090+547=3637
(20408-12599)*47-(12300*12-89568)=308991
1)20408-12599=7809
2)7809*47=367023
3)12300*12=147600
4)147600-89568=58032
5)367023-58032=308991