55+4 = 67+2 = 40+50 = 80 – 30 = 70 – 20 =
55+40 = 37+60= 40+28 = 76 +10 = 40+8=
83 – 20 = 74 – 60 = 37 – 3 = 63 – 20 = 46 – 10 =
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