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

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Boy Mow Chau
Boy Mow Chau's answer
317 answers (Tutor Details)
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Boy Mow Chau
Boy Mow Chau
4 years ago
… believe that method should be right, but do check for calculation errors ...

for the last part of the question, can treat as binomial because …
- the 5 trials are independent
- can treat as two possible outcomes, getting a -1, and not getting a -1.
- probability of getting a -1 remains constant for all the trials.