If a letter is chosen at random from the English alphabet, find the probability that the letter is (i) a vowel (ii) a constant
given: a letter is chosen at random from English alphabet
formula: 
total possible outcomes of selecting an alphabet is 26C1
therefore n(S)=26C1=26
(i) let E be the event that a vowel has been chosen
E= {a, e, i, o, u}
n(E)= 5C1=5
(ii) let E be the event that a consonant is chosen
E= all alphabets - {a, e, i, o, u}
n(E)= 21C1=21
32