you got the number 9 wrong (6 segments)
following error then on Sam's one from 89 to 17 (5+1 must be 5+2)
Sam's step from 17 to 8 then... Hmmm, I can not even guess what that means, but correct would be 2 to turn the one off + 3 to make an eight of the seven.

So we have in total of 32 (last step in Sam's calculation to turn the eight off is in my book a 7 and not a 3+4, but hey, can't tell what you do there)

When we consider the 9 for Max (rest of your calculations are correct) we have 2 more in Max's result ;\)

so I guess you tee off in a minute?

 Code:
  Sam   Max
  7+6  (7+6)*2  
89
  5+2  (2+4)*2
17
  2+3  (7)*2
8
    7
  =32   =52   result: 20
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