15,37*7,88-9,37*7,88+15,37*2,12-9,37*2,12
15,37*7,88-9,37*7,88+15,37*2,12-9,37*2,12=
7,88(15,37-9,37)+2,12(15,37-9,37)= 7,88*6+2,12*6=6(7,88+2,12)=6*10=60