All solutions here are SUGGESTED. Mr. Teng will hold no liability for any errors. Comments are entirely personal opinions.

(i)

Required Probability

(ii)

Required Probability

(iii)

Case 1: 2 same letter and 2 different digits

Case 2: different letter and 2 same digits

Case 3:3 same letter and 2 same digits

Required Probability

(iv)

Case 1: 2 different consonants, 1 vowel & 1 even digit

Case 2: 2 same consonant, 1 vowel & 1 even digit

Required Probability

### KS Comments:

This question is not that easy. A lot of thinking is required; but that is the case with all permutation questions. I strongly suggest students to not spend too much time on permutation questions and come back to solve it later.

[…] big topic by itself. What you learnt in Permutation & Combination is used in probability (e.g. A’levels 2013 P2 Q11), and probability is used in all the distributions you will be learning, lastly normal […]