If 4-digit numbers greater than 5,000 are randomly formed from the digits 0, 1, 3, 5. and 7. what is the probability of forming a number divisible by 5 when,
(i) the digits are repeated?
(ii) the repetition of digits is not allowed?

Explanation

To solve the problem, we need to find the probability of forming a 4-digit number greater than 5,000 that is divisible by 5, under two different conditions: (i) when digits can be repeated and (ii) when repetition of digits is not allowed.

### Part (i): Digits can be repeated

1. **Identify the valid starting digits**:
- The first digit must be greater than 5,000. Therefore, the valid choices for the first digit are 5 and 7.
- **Choices for the first digit**: 2 (5 or 7).

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