One of the ten available keys opens the door. If we try the keys one after another, then find the following
(i) the probability that the door is opened in the first attemt.
(ii) the probability tht the door is opened in the second attempt.
(iii) the probability that the door is opened in the third attempt.
(iv) the probability that the door is opened in the tenth attempt.

Explanation

To solve the problem step by step, we will calculate the probabilities for each of the four parts of the question.

### Given:
- Total keys = 10 (1 original key + 9 fake keys)

### (i) Probability that the door is opened in the first attempt:
To open the door in the first attempt, we need to pick the original key directly.

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