Since Governor Sandoval gave 12 commencement addresses, twice the number that Governor Hawkins gave, Governor Hawkins gave 12/2 = <<12/2=6>>6 commencement addresses.
The two of them gave 6+12 = <<6+12=18>>18 commencement addresses in total.
Governor Sloan gave ten more commencement addresses than Governor Sandoval, a total of 12+10 = <<12+10=22>>22 commencement addresses.
The three of them gave 22+18 = <<22+18=40>>40 commencement addresses.
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