IBDP Math (AA HL 1.10) Permutations & Combinations Exam Questions Video Series

In this video, EdXP's Math guru, Dr Boon, has carefully curated a set of Permutations & Combinations questions from past IBDP exams papers and he will be showing you the techniques, tips and tricks required to solving these questions. The teaching will be in a progressive manner so that you can apply what you've learnt from the previous questions.

Dr Boon is an experienced and highly sought after IBDP Math tutor. He has tutored more than 1000 students from Singapore, China, Hong Kong, USA and the UK. More than half of his students have gone on to score a 7 for their IB exams and their average IB overall score is 42.7

[juli]

For the 3rd questions (Q.9 b)) there are 3 sheep remaining and 4 pens remaining. Shouldn't we use permutation 4P3 here rather than 4 factorial? If my observation is wrong then could you please explain why you put 4! there instead?