Assume that both the coin and the die are fair and that the problem statement means to say "a six-sided die numbered 1 through 6".
The probability of flipping "tails" is 1 out of 2 or (1/2).
The probability of rolling a number greater than 5 is 1 out of 6 or (1/6).
Then the probability of obtaining "tails" and then a number greater than 5 is written as
P(Tails, N > 5)and equal to (1/2) times (1/6) or (1/12).
Just in case there is an 8-sided die numbered 1 through 6 (with 2 sides left blank), the probability of obtaining "tails" and then a number greater than 5 is written as P(Tails, N > 5) and equal to (1/2) times (1/8) or (1/16).
For an 8-sided die numbered 1 through 8, the probability sought would be P(Tails, N > 5) and equal to (1/2) times (3/8) or (3/16).
