George picked at first 12 because 36 / 3 = <<36/3=12>>12.
George picks 22 by the end because 12 + 10 = <<12+10=22>>22
Billy picks 66 by the end because 36 + 10 = <<36+10=46>>46
In total they picked 68 because 22 + 46 = <<22+46=68>>68
On average they picked 34 because 68 / 2 = <<68/2=34>>34
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