We are given a table that partially represents the outcomes of tossing two unbiased coins. We need to complete the table and then calculate the probabilities of the following events: getting two heads, getting different outcomes, and getting at least one tail.
2025/6/26
1. Problem Description
We are given a table that partially represents the outcomes of tossing two unbiased coins. We need to complete the table and then calculate the probabilities of the following events: getting two heads, getting different outcomes, and getting at least one tail.
2. Solution Steps
(a) Completing the outcome table:
The rows represent the outcome of Coin 2 and the columns represent the outcome of Coin
1. The entries in the table represent the combined outcomes.
| | Coin 1 (H) | Coin 1 (T) |
|--------|------------|------------|
| Coin 2 (H) | HH | HT |
| Coin 2 (T) | TH | TT |
(b) Calculating probabilities:
(i) Probability of getting two heads (HH):
There is one outcome (HH) out of four possible outcomes (HH, HT, TH, TT).
Therefore, the probability is .
(ii) Probability of getting different outcomes:
The different outcomes are HT and TH. There are two such outcomes out of four possible outcomes.
Therefore, the probability is .
(iii) Probability of getting at least one tail:
The outcomes with at least one tail are HT, TH, and TT. There are three such outcomes out of four possible outcomes.
Therefore, the probability is .
3. Final Answer
(a) The completed table is:
| | Coin 1 (H) | Coin 1 (T) |
|--------|------------|------------|
| Coin 2 (H) | HH | HT |
| Coin 2 (T) | TH | TT |
(b) The probabilities are:
(i) Probability of getting two heads:
(ii) Probability of getting different outcomes:
(iii) Probability of getting at least one tail: