Probability Tree Diagrams
In this video, I introduce you to drawing tree diagrams as a way of simplifying calculations when combining probabilities.
It is important that you see all three questions as they differ in style. I also introduce you to the notation of conditional probability.
1) A bag contains 5 red sweets and 3 blue sweets. Two sweets are drawn at random i) with replacement and ii) without replacement.
2) Susan has the option of taking one of three routes to work A, B or C.
The probability of taking route A is 35%, and B is 25%.
The probability of being late for work if she goes by route A is 10% and similarly by route B is 5% and route C is 2%.
3) A normal six sided fair die is thrown until a six is scored and then no more throws are made. The process continues up to a maximum of three throws.
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