500 + (300/23) = 513.0434782608695652173913 recurring (that is, 513.04347826086956521739130434782608695652173913...)
13 + 23 + 12 + 7 = 55
90
12 + 15 + 63 + 12 + 24 + 34 + 23 + 15 = 198
12
The answer is n + 1610.
50
23 + 10 - 12 = 21
12 + 23 + 45 + 67 + 16 + 18 + 45 = 226
4*12 + 3*23 = 117.
60.
88