Boy Mow Chau's answer to Olivia's Junior College 2 H2 Maths Singapore question.

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Boy Mow Chau
Boy Mow Chau's answer
317 answers (Tutor Details)
1st
(ii) first consider the ways to select the gemstones, then multiply by the ways to place them in the required manner.

(iv) have to consider all the different possible combinations of gemstones, work out the ways for each combination, then total up.

please check for calculation mistake.