Consider the case of Bill
He can have 6C1*6C1= 36 possibilities for the throw.
Same for Jane, She can have 6C1*6C1= 36 possibilities for the throw.
Thus total possible cases= 36*36= 1296
Number of ways both Bill and Jane get a 2:
Bill: (1,1) and Jane: (1,1) = 1
This is same for the case when the both get 12:
Bill: (6,6) and Jane: (6,6) = 1
Number of ways both Bill and Jane get a 3:
Bill: (1,2|2,1) and Jane: (1,2|2,1) = 2C1*2C1= 4
This is same for the case when the both get 11:
Bill: (5,6|6,5) and Jane: (5,6|6,5) = 4
Number of ways both Bill and Jane get a 4:
Bill: (1,3|3,1|2,2) and Jane: (1,3|3,1|2,2) = 3C1*3C1= 9
This is same for the case when the both get 10:
Bill: (4,6|6,4|5,5) and Jane: (4,6|6,4|5,5) = 9
Number of ways both Bill and Jane get a 5:
Bill: (1,4|4,1|2,3|3,2) and Jane: (1,4|4,1|2,3|3,2) = 4C1*4C1= 16
This is same for the case when the both get 9:
Bill: (3,6|6,3|5,4|4,5) and Jane: (3,6|6,3|5,4|4,5) = 16
Number of ways both Bill and Jane get a 6:
Bill: (2,4|4,2|3,3|1,5|5,1) and Jane: (2,4|4,2|3,3|1,5|5,1) = 5C1*5C1= 25
This is same for the case when the both get 8:
Bill: (2,6|6,2|5,3|3,5|4,4) and Jane: (2,6|6,2|5,3|3,5|4,4) = 25
Number of ways both Bill and Jane get a 7:
Bill: (3,4|4,3|2,5|5,2|6,1|1,6) and Jane: (3,4|4,3|2,5|5,2|6,1|1,6) = 6C1*6C1= 36
Total number of ways for draw:
2*1 + 2*4 + 2*9 + 2*16 + 2*25 + 36= 146
Thus total ways in which either Bill or Jane wins:
1296-146= 1150
Jane will win in half the cases whereas Bill will win in half the cases
Hence Jane wins in 1150/2= 575 cases
Thus total probability
575/1296
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