The unbiased dice is tossed until a number greater than 4 appear. What is the probability that an even number of tosses is needed?

Explanation

To find the probability that an even number of tosses is needed until a number greater than 4 appears when rolling an unbiased die, we can follow these steps:

### Step 1: Identify the Success and Failure Outcomes
When rolling a die, the outcomes are 1, 2, 3, 4, 5, and 6. We define success as rolling a number greater than 4, which includes the outcomes 5 and 6. Therefore:
- **Success (S)**: {5, 6} → 2 favorable outcomes
- **Failure (F)**: {1, 2, 3, 4} → 4 favorable outcomes

### Step 2: Calculate the Probabilities
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