I can't get get the correct answer for a question. The question is: Bob and Roy play a game in which they roll 2 unbiased 6-faced dice. The first one who rolls a sum of 6 wins.

a) What is the probability that Kassanthra wins on her second roll?

b) What is the probability that George wins on his second roll?

My answers:

a) (5/6)(1/6)=0.139

b) (1-0.139)(5/6)(1/6)=0.120

Textbook answers:

a) 0.103

b) 0.0887

What am I doing wrong?