Question 1144875

I also got 9

I followed the procedure outlined on Wikipedia (add odd digits, multiply by 3, then add even digits, take result mod 10, if this value is nonzero, subtract from 10, otherwise use 0):

Details:
5+1+2+3+2+7 = 20
20 * 3 = 60
60 + (1+3+0+6+1) = 71

71 mod 10 = 1 ---> nonzero so check bit is 10-1 = 9