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. z.
70-30= 53+8= 28+9= 26-20= 30-9=
100-90= 7+48= 38+30 52+8= 47+20= 68+15= 56-40=
90-40= 30+14= 64+7= 5+56= 47-13=
90-70= 64+6= 27+4= 30+36= 37-30=
50-30= 18+5= 21+30= 45+10= 65-4=
50+50= 20+68= 10+76= 51+24= 65-4=
60+30= 46+5= 28+4= 69-7= 98-8=
30+70= 76+9= 81+17= 38-16= 88-80=
57-8=
38+50=
50+39= 16+80=
41-40=
68-30=
59-30=
87-40=
85-60=
84-80= 71-30=
95-60=
57-20=
73-40= 99-10=
61-60= 84-10=
83-70=
84-60=
86-30=
21-10=
39-20= 79-40=
88-30=
91-40= 75-50=
87-40=
96-80= 67-9=
26-5= 80-44=
86-7=
52-20=
70-5=