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Question
If a letter is chosen at random from the English alphabet, find the probability that the letter is a vowel .
Solution
We know that there are 26 letters in the English alphabet.
So, total number of elementary events, n(S) = 26
Out of the five vowels of the English alphabet (a, e, i, o, u), one vowel can be chosen in 5C1 ways.
So, favourable number of events = 5C1 = 5
Hence, required probability = \[\frac{5}{26}\]
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