Answer: 3/8
Step-by-step explanation:
P(T = 1) is the notation that means "The probability of getting exactly one tail". The table shows 3/8 in the bottom row, under the "1" in the top row. So that's why P(T = 1) = 3/8
Or it might make more sense to say P(one tail) = 3/8 so we don't have too many equal signs going on.