how many items are in the event "exactly one tail" when a coin is flipped 3 times
When a coin is flipped 3 times, there are 2 possible outcomes for each flip: either a head (H) or a tail (T).
To find the number of items in the event "exactly one tail," we need to find the combinations where only one outcome is a tail and the other two are heads.
Let's denote H as a head and T as a tail.
The possible outcomes with exactly one tail are:
1. HHT
2. HTH
3. THH
Thus, there are 3 items in the event "exactly one tail" when a coin is flipped 3 times.