Introduction:
In this problem, we are given the word "probability" and we need to find the probability of selecting a vowel at random from this word. A vowel is a letter that represents a speech sound made with the vocal tract open. In the English alphabet, the vowels are 'a', 'e', 'i', 'o', and 'u'.

Given:
Word: probability

Solution:
To find the probability of selecting a vowel at random from the word "probability", we first need to determine the total number of letters in the word and then count the number of vowels.

Counting the total number of letters:
The word "probability" has a total of 11 letters.

Identifying the vowels:
Now, let's identify the vowels in the word "probability":
- 'o'
- 'a'
- 'i'
- 'i'

Counting the number of vowels:
The word "probability" has a total of 4 vowels.

Calculating the probability:
The probability of selecting a vowel at random can be calculated using the formula:
Probability = Number of favorable outcomes / Total number of possible outcomes

In this case, the number of favorable outcomes is the number of vowels in the word, which is 4. The total number of possible outcomes is the total number of letters in the word, which is 11.

So, the probability of selecting a vowel at random from the word "probability" is:
Probability = 4/11

Final Answer:
The probability of selecting a vowel at random from the word "probability" is 4/11.