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

(i)

Firstly, the probability of picking a free gift is constant. Secondly, there is only two possible outcomes, i.e., the packets either contain a free gift or do no contain a free gift.

(ii)

(iii)

Since is large, approximately.

### KS Comments:

This is a simple question on binomial distribution and approximation. Students had to be cautious to answer (i) in context.

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