first you do parthesis (27/9) = 3 then you subtract from 10 [10-3] = 7 then multiply 3 (this is last because it is outside the parenthesis and [ ]. 7 x 3 = 21
100% of the rolls would be less than 13. The highest number on one die is 6, so even if you roll 2 dice the sum of both dice will always be lower than 13. It's a 1:1 probablility.
