Three identical coins are tossed together. What is the probability of obtaining :
all heads ?

Answer

To find the probability of obtaining all heads when three identical coins are tossed, we can follow these steps:

### Step 1: Determine the Sample Space
When three coins are tossed, each coin can either land on heads (H) or tails (T). The total number of outcomes can be calculated as follows:

- Each coin has 2 outcomes (H or T).
- For 3 coins, the total number of outcomes is \(2^3 = 8\).

The sample space (all possible outcomes) is:
1. HHH
2. HHT
3. HTH
4. THH
5. HTT
6. THT
7. TTH
8. TTT

### Step 2: Identify Favorable Outcomes
Next, we need to identify the favorable outcomes for the event of getting all heads (HHH).

- There is only **1 favorable outcome**: HHH.

### Step 3: Calculate the Probability
The probability \(P\) of an event is given by the formula:

\[ P(\text{event}) = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} \]

Substituting the values we found:

\[ P(\text{all heads}) = \frac{1}{8} \]

### Final Answer
The probability of obtaining all heads when three identical coins are tossed is \(\frac{1}{8}\).

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